Critical Reasoning

“We are still masters of our fate. We are still captains of our soul.”*

• Winston Churchill*

Critical Reasoning is a favorite of people who love to argue. Here, your talents at arguing, breaking apart reasoning, and finding weak points to attack or defend will shine.

This section is one of the most important on the GMAT. Anyone who can argue persuasively by logically evaluating an issue on its merits and responding to its strength and weaknesses has the critical thinking needed to be a good business manager.

Business managers must evaluate arguments and proposals with a critical eye because not all business deals recognize their parties equally. Sometimes you have to argue your point to be heard.

This section accounts for a full 30% of your verbal section score, and contains 12 to 13 questions.

To answer questions correctly in this section, it is very important to identify the various parts of critical reasoning questions.

The Question

Critical reasoning questions are easy to understand as they are very short and usually begin with the following instructions: For each question, select the best of the answer choices given.  A critical aspect to answering the questions lies in the instruction itself. Note that you are not told to select the perfect answer, but to select the best answer available from the choices given. This is an important distinction since you don’t want to immediately discount any one choice simply because it doesn’t coincide perfectly with the ideal answer you may have in mind.

Having said that, it is a good idea to answer the question in your head before looking at the answer choices. This can help you solidify your thinking before being influenced by the sometimes tempting answer selections. Remember, though, if you don’t find a perfect match, quickly reevaluate the question and look for the best answer from the available options.

The Short Passage

The next part of the question is the short passage. The passage is drawn from a variety of areas including casual conversation, natural sciences, and more. You may have no experience with the topic, but that is okay, as you do not need outside knowledge to understand the question. In fact existing knowledge can mislead you or bias your answer. So try to understand the question based on the information provided.

There are several different types of critical reasoning questions.  You may be asked to identify a point that will strengthen or weaken the argument, or to make a deduction from the passage.

Choosing the right answer can be difficult, especially when some questions have two or more correct answers; one will be superior over the other though Again, the goal is to choose the best answer, Here are a few steps that can help.

1.     Before you read the short passage, read and understand the question as thoroughly as possible because your understanding of the short passage will depend on the question. If you know what you are supposed to look for before reading the short passage, you will be able to take a more logical approach while reading.

2.     Once you understand the question, read the short passage. Most critical reasoning questions require you to identify parts of the argument, so read the passage actively and critically. Understanding the strengths and weaknesses of the argument will help you answer the question accurately.

3.     Since you know the question and have read the passage, do yourself a favor by first answering the question without looking at the answers provided. For example, if the question wants you to find a statement to weaken the argument, review the passage and determine what could weaken it.

4.     If you were able to determine an answer, then look at the answers provided for a match. If you couldn’t come up with an answer, skim through each answer provided, keeping the passage in mind. Quickly eliminate the answers that do not apply. Once you select an answer, reread the question and the passage to be certain about your answer.

Splitting Up the Argument

Of course, reading a passage and drawing your own conclusions is one thing; reading the answers and figuring out the best one in relation to the passage is another thing altogether.

For Critical Reasoning, understanding the logic behind the argument is imperative in order to answer the questions. Doing this involves identifying the different components of the passage. On the GMAT, the argument is a claim supported by reasoning.

•       The Earth is flat because it looks flat.

This was a common argument centuries ago, and it carries the same components that an author uses when pushing across his or her argument. The three main components of an argument are: the conclusion, the evidence, and the assumption(s). We’ll deal with the conclusion and evidence first since they are the easiest to identify.

1.     The conclusion: This is the author’s claim or the point that he or she is trying to make. In this example, the Earth is flat is the conclusion.

2.     The evidence: this is what the author uses to back up his or her claim. Here, It looks flat is the evidence.

While reading Critical Reasoning questions, it is important that you identify the conclusion from the evidence provided. First, despite its name, the conclusion does not always comes at the end of a passage as in the above example. It may come at the beginning, it may follow the evidence, or it may, in fact, be at the end.

As a result, finding the conclusion in a long passage can be difficult. Thankfully, a few keywords can ease the process. The words therefore, us, as a result, hence, clearly, so, and consequently are examples of conclusion keywords. We know this because their meanings essentially signal the beginning of a conclusion.

•       When I look around I see flatness, (therefore, thus, as a result, hence, so, consequently) the Earth is flat.

•       Clearly, the Earth is flat because all I see around me is flat ground.

These two sentences show how certain keywords signal the conclusion. In the first sentence, the words therefore, thus, as a result, hence, so, and consequently are interchangeable since they all signal the conclusion the earth is flat. In the second sentence, the word clearly signals the conclusion.

Likewise, evidence keywords help you identify the evidence. The words because, since, and for are examples of evidence keywords.

•       The Earth is flat because all I see around me is flat ground.

•       Since all I see around me is flat ground, the Earth is therefore flat.

•       The Earth is flat for all I see around me is flat ground.

The use of the words because, since, and for signal the evidence in the above sentences. Obviously, these are very easy questions to answer correctly because they contain just one line, one quick piece of evidence, and one quick conclusion.

However, searching for evidence keywords can be effective for longer passages. The following sample passage helps us understand how.

Global warming is a serious problem for our planet. All around us, the Earth is heating up to record temperatures, which can seriously affect our way of life. Since global warming became a problem after the advent of the automobile, it can clearly be ascertained that the invention of the automobile has caused global warming. Only the elimination of the automobile will then fix the problem of global warming.

This relatively long passage includes some fluff and secondary points. Where is the evidence and conclusion? Let’s look again, with the evidence keywords underlined.

Global warming is a serious problem for our planet. All around us, the Earth is heating up to record temperatures, which can seriously affect our way of life. Since global warming became a problem after the advent of the automobile, it can clearly be ascertained that the invention of the automobile has caused global warming. Only the elimination of the automobile will then fix the problem of global warming.

Now we see why identifying an easy passage like the earth is flat because all I see is flat ground is such an effective tool to use to figure out a passage. While reading the above passage, take out everything that is not needed and condense it into a short sentence that includes the evidence and the conclusion.

If done properly, your short sentence should read something like this:

•       Since global warming became a problem after the automobile was invented, it is clear that the automobile is the cause of global warming.

We have taken a complicated passage and condensed it into a short sentence, eliminating the useless information. This method uncovers the conclusion and evidence quickly and easily.

Now that we understand the conclusion and the evidence, let’s look at the third element of an argument:

3.     The assumption (s): This is what the author assumes to be true when formulating evidence for the conclusion. We will discuss how to identify an assumption a bit later.

Although only one type of Critical Reasoning question specifically asks you to identify the assumption, this step is an important part of understanding the argument itself, and is therefore crucial to answering any of the critical reasoning questions.

Brandon's Tip

So, what exactly is an assumption? An assumption is anything the author assumes is true and uses to support the argument. This assumption is often pertinent to the validity of the argument, and if proven to be untrue, would completely destroy the entire argument.

Let’s look at our argument about the Earth being flat. We’ve already determined that the evidence the author uses to support the argument is the fact that it looks flat. So, what is the assumption behind the author’s decision to use this particular piece of evidence? To answer this question, ask yourself why the evidence supports the conclusion, and put your answer in statement form so that it looks like this:

•       The evidence supports the conclusion because ___________.

Your answer to this question will be the assumption of the argument. In our example, the statement will read:

•       The fact that the Earth looks flat supports the argument that the Earth is flat

The assumption behind the argument is the idea that what something looks like and what it actually is are always the same. Of course, anyone who has ever heard the expression, “don’t judge a book by its cover,” or has discovered that a seemingly loyal friend has betrayed him knows that this isn’t true; nevertheless, it is the assumption that this particular argument is based on. Assumptions do not have to be true, but the strength of the argument will depend on the believability of the assumption(s) behind it.

Some of the arguments on the GMAT will have more than one assumption. Let’s look at another example:

3-D movies draw in twice as many audience members as their standard counterparts even though they are more expensive. Robots from Outer Space is a 3-D movie. It will make twice as much money as Monkeys of Madrid despite the bad economy.

Let’s use our technique to determine the underlying assumptions of the argument.

First, we must identify the conclusion and evidence. Remember, the conclusion is what the author is trying to prove. Despite the absence of keywords, it is clear that the author wants you to believe that the 3-D movie Robots from Outer Space will make twice as much money as Monkeys from Madrid despite the bad economy. To support this claim, the author provides the following evidence;

•       Robots from Outer Space is a 3-D movie.

•       3-D movies draw in twice as many audience members as their standard counterparts even though they are more expensive.

To determine the assumptions that this argument is based on, we must ask ourselves why the evidence supports the claim. In other words, what else has to be true in order for this argument to make sense. Let’s fill in the blank.

The fact that 1) Robots from Outer Space is a 3-D movie and 2) 3-D movies draw in twice as many audience members as their standard counterparts even though they are more expensive supports the argument that Robots from Outer Space will make twice as much money as Monkeys from Madrid despite the bad economy because: ___________________.

That’s a mouthful and probably wouldn’t pass a grammar check, but it serves our purpose of identifying the hidden assumptions. Here, you should have filled in the blank with some variation of the following:

The fact that 1) Robots from Outer Space is a 3-D movie and 2) 3-D movies draw in twice as many audience members as their standard counterparts even though they are more expensive supports the argument that Robots from Outer Space will make twice as much money as Monkeys from Madrid despite the bad economy because: 1) The dimension of the movie is the only factor one considers when deciding which one to watch and 2) The economy has no effect on how much money one is willing to spend on a movie ticket.

Now that we have covered the scope of the questions and how they can be broken up into smaller bits to help you to make an informed decision, we will move on to the types of critical reasoning questions that you will be asked on the GMAT.

Assumption Questions

The first type of question is the assumption question. In this type of question, the author makes an assumption about something, and it is up to you to select the best of the answers provided based on that assumption.

Assumption questions are often presented in one of the following ways:

•       Which of the following is an assumption…

•       The argument depends on which of the following assumptions?

•       The conclusion drawn above is based on the assumption that…

•       The conclusion above is properly drawn if which of the following is assumed?

First, find anything that goes beyond the scope of the argument. Often, each argument is written within a narrow set of parameters. The wrong answers go beyond these simple parameters.

Second, wrong answers to assumption questions often use extreme language that goes beyond the claim of the author.

Lastly, wrong answers do not support the argument. Remember, an assumption must support the argument, and an assumption must be true for the argument to be valid.

To determine where the author is going with the assumption, ask yourself the following 3 questions;

1.     Which of the following, if added to the passage, makes the conclusion more valid?

2.     Which of the following does the author assume?

3.     The validity of the argument depends on which of the following?

Let’s look at a few examples.

The class action suit against Walkers claims that the company failed to give its employees adequate break times. Since it is true that workers were only allowed a thirty minute break for every six hours of labor, the class action suit is more than justified. After all, it takes more than half an hour to get in one’s car, drive to the nearest restaurant, stand in line, and get back to Walkers.

The argument above is based on which of the following assumptions:

A.    Most people bring their lunches to work because leaving the office for lunch is so time-consuming.

B.    The amount of time an employee gets for a break should be based upon the total amount of time it takes to go out for lunch.

C.    Laws are in place that mandate that employers give their employees at least an hour break for every six hours worked.

D.   Employers should always follow company policy when deciding upon break times; location of nearby restaurants and personal employee preferences should not be a factor.

E.    Since so many employees decided to be a part of the class action suit, it must be a valid claim.

The author’s argument here that the class action suit against Walkers regarding break times is a valid one since the workers barely have enough time to go out to lunch and return before their thirty minute break is up. Since the only piece of evidence the author presents is the amount of time it takes one of Walker’s employees to go get take-out, we have to assume that this is the underlying assumption of the argument. If there was any doubt, a look at the other choices should confirm B to be the correct choice:

A. Most people bring their lunches to work because leaving the office for lunch is so time-consuming.

Eliminating this first choice should have been a no-brainer. Since the main piece of evidence the author uses deals with the amount of time it takes to go out for lunch, this statement regarding the number of people who prefer to eat in is in direct opposition to the author’s claim.

C. Laws are in place that mandate that employers give their employees at least an hour break for every six hours worked.

This choice is tempting because if it were true, it would certainly strengthen the argument, but remember, this is not a strengthen question, it’s an assumption one. Since this information is not even mentioned in the argument, it cannot possibly be the basis for the argument,

D. Employers should always follow company policy when deciding upon break times; location of nearby restaurants and personal employee preferences should not be a factor.

This option also opposes the author’s claim. The purpose of the passage is to explain why Walker’s is legitimately being sued; this choice supports Walker’s company policy and can be immediately eliminated.

E. Since so many employees decided to be a part of the class action suit, it must be a valid claim.

This option goes beyond the scope of the argument. There is no mention of how many people are part of the class action suit; therefore, it cannot possibly be the foundation for the argument.

Ø  More Practice from the GMAT**®** Review 13****th Edition: Questions 41, 48, 77, 83, 96

Strengthening and Weakening Questions

These are the most common types of critical reasoning questions that you will face on the GMAT. Obviously, these questions are pretty easy to understand. You need to analyze what may strengthen or weaken the argument made by the author. As with the previous type of question, and any other critical thinking question on the GMAT, breaking the passage apart is the first step.

Strengthen questions are often presented in one of the following ways:

•       Which of the following, if true, most strongly justifies the claim…

•       Which of the following, if true, provides the most support for the argument above?

•       Which of the following, if true, would most strengthen the conclusion drawn?

•       Which of the following, if true, provides the strongest grounds for…

Weaken questions are often presented in one of the following ways:

•       Which of the following, if true, most seriously weakens the argument above?

•       Which of the following, if true, most seriously calls into question…

•       Which of the following, if true, casts the most serious doubt on the argument above?

•       Which of the following, if true, most strongly indicates that the logic of the prediction is flawed?

When trying to strengthen the argument, pick out the choice that will best fill in the key assumption and give it more merit. When you want to weaken an argument, pick the choice that will undercut the key assumption.

Let’s look at an example:

The claim that fast food contributes to obesity is simply absurd. I personally eat fast food every day and am well within the normal range for weight and body mass index. As long as you exercise regularly and eat fast food in moderate portions, there’s no reason to worry about fast food restaurants making you gain weight.

Which of the following, if true, would strengthen the argument above?

A.    People who eat out three times a week are no more obese than those who eat at home.

B.    Fast food restaurants have recently made an attempt to offer healthier choices.

C.    Research shows that exercise and moderation are the most important factors in maintaining a healthy weight—more important even than the kinds of food one eats.

D.   Some people abstain from fast food but are still obese.

E.    Some fast food is actually healthier than home-cooked meals.

The author concludes that since he has a normal weight and BMI and eats fast food every day, then fast food does not cause obesity. He goes on to say that as long as one eats in moderation and exercises, then fast food will not have an impact on his/her weight. Although his personal experience with fast food is not enough to make such a broad generalization, if it is true that research has proven that exercise and moderation are more important factors than the nutritional value of the food one eats, then his claim is valid. Answer C is correct.

Now, let’s look at the other choices:

A. People who eat out three times a week are no more obese than those who eat at home.

This choice introduces weak, anecdotal evidence that lacks the specific details needed to strengthen the argument. We have no clue who these people are, where they are eating out three times a week, what portion sizes they’re consuming, or whether or not they exercise. Therefore, this “evidence” proves nothing in relation to the potential impact of fast food on weight.

B. Fast food restaurants have recently made an attempt to offer healthier choices.

Again, this choice lacks the detail and specificity needed to strengthen the argument. It may be true that fast food restaurants are making attempts to offer healthier choices, but we don’t know how healthy they are, whether consumers are taking advantage of these options, and if they are being consumed in moderation or in conjunction with adequate exercise. Therefore, this detail has no bearing on the argument in question.

D. Some people abstain from fast food but are still obese.

This choice offers a faulty comparison. Just because some obese people eat things other than fast food doesn’t mean that fast food cannot have an impact on weight.

E. Some fast food is actually healthier than home-cooked meals.

Even if this is true, we have no way of inferring from the statement which types of fast food are healthier. Furthermore, just because some types are healthier does not mean that fast food in general does not cause obesity. This choice is much too vague to impact the argument.

Now, consider this question:

The “Kids’ Night” promotion at Burgers-n-More, a local fast food restaurant, has been a huge success. The last time I visited the restaurant on Kids’ Night, the place was packed with parents looking to get a free meal for their children. This promotion will no doubt increase Burgers-n-More’s overall profits.

Which of the following, if true, would most seriously damage the argument above?

A.    Burgers-n-More gives out an average of 150 free meals during each Kids Night.

B.    More parents attend Pizza King on Kids Night than Burgers-n-More.

C.    The same total number of patrons visit Burgers-n-More now as before the promotion began, but more come on Kids Night to take advantage of the promotion.

D.   In a recent survey, kids reported that they prefer Burgers-n-More to any other fast food restaurant.

E.    Burgers-n-More recently stopped promoting its Kids Night on the local radio station.

The author concludes that the Kids Night promotion will increase the overall profits of Burgers-n-More. Although there are no key words that indicate this is the conclusion, it is what the author wants you to believe. It has not happened yet – the author uses the word will - so there can be no concrete evidence. From the author’s perspective, the more parents that buy food from the restaurant, the higher the profits for Burgers-n-More.

But, of course, things aren’t always that simple. There are other factors that could influence the success of the promotion. For instance, if the promotion is simply steering its regular customers to visit the restaurant on a certain night when free food is available, rather than drawing in new customers, as proposed by choice C, then that would seriously weaken the author’s argument…and Burgers-n-More’s bottom line. Choice C is correct. Let’s examine the other choices:

A. Burgers-n-More gives out an average of 150 free meals during each Kids Night.

Although that does seem like a lot of free food to be giving away, we can’t derive a conclusion from this fact alone. We don’t know how many adult meals, soft drinks, or other profit-makers the restaurant sold in addition to giving away the free kids meals.

B. More parents attend Pizza King on Kids Night than Burgers-n-More.

This is a classic case of a faulty comparison thrown in as a distraction. Although it doesn’t sound good for Burgers-n-More that parents prefer Pizza King’s promotion, that doesn’t eliminate the possibility that Burgers-n-More’s Kids Night is increasing its own profit margins.

D. In a recent survey, kids reported that they prefer Burgers-n-More to any other fast food restaurant.

You probably eliminated this choice first as it seems to strengthen rather than weaken the argument. Keep in mind, though, that just because kids report that they prefer a restaurant doesn’t mean their parents plan on taking them there. This answer neither weakens nor strengthens the conclusion.

E. Burgers-n-More recently stopped promoting its Kids Night on the local radio station.

Although it would stand to reason that the more publicity the promotion received, the more patrons would attend the promotion, we have no proof of how effective the radio promotion was in increasing sales. Therefore, it is not the best choice.

Ø  More Practice from the GMAT**®** Review 13****th Edition: Questions 11, 23, 40, 67, 118 (strengthen)

Ø  More Practice from the GMAT**®** Review 13****th Edition: Questions 25, 32, 37, 58, 62 (weaken)

Flaw Questions

Flaw questions ask about the structure of the argument, rather than the topic. They look at the way terms are defined, the way the premises support the conclusion, or omissions made by the author.

Flaw questions are often presented in one of the following ways:

•       The argument is flawed in that it ignores the possibility of…

•       Which of the following points is the most serious logical flaw in the argument?

•       The argument is most vulnerable to criticism on which of these grounds?

•       The argument is most vulnerable to the objection that it fails to…

Do not confuse flaw questions with weakening questions. Although they may seem similar, in weakening questions you are supposed to find additional information to weaken the argument if it is true. In a flaw question, the evidence is not very supportive of the conclusion, and you as the test taker must explain why.

As usual, break up the argument to find out how best to determine why it is flawed.

Here is an example:

Proponents of the law against texting and driving attribute up to 20 percent of all accidents to sending text messages while operating a motor vehicle. This alarming statistic must be true since many accidents are caused by teenagers, and adolescents text more than any other segment of the population.

Which of the following indicates the most serious flaw in the author’s reasoning?

A.    He clearly has a moral issue with the teenage population.

B.    He does not take into consideration other possible causes of teen accidents.

C.    He doesn’t include information about why texting causes accidents.

D.   There are no specific examples to support his claim.

E.    He fails to acknowledge the rights of teenagers.

The author makes the argument that since many accidents are caused by teenagers, and teenagers text more than any other age group, then texting must be to blame for 20% of all accidents. This sweeping overgeneralization fails to mention other causes of teenage accidents, which is the major flaw of the argument, as indicated in option B.

Let’s analyze the other choices:

A. He clearly has a moral issue with the teenage population.

Although it may seem that the author is biased against teenagers, he makes no comment that could be construed as a moral criticism.

C. He doesn’t include information about why texting causes accidents.

Although information about why texting causes accidents may be helpful, it would do nothing to prove or disprove the argument - that texting causes 20% of accidents.

D. There are no specific examples to support his claim.

Specific examples are not necessary for statistical claims. Stories about individual car accidents would do nothing to support the argument.

E. He fails to acknowledge the rights of teenagers.

Although it may be true that the author doesn’t address the rights of teenagers, this is an irrelevant observation since it has no impact on the basic assumption of the argument- that texting is to blame for a fifth of all accidents.

Here’s another…

There is definitely not a behavior problem at Gateview High School as implied in the editorial in yesterday’s newspaper. I am an Honors student at GHS and take all advanced classes, so you can take it from me when I say that the kids in my class pay attention and work really hard. In fact, all my friends are so concerned with earning high grades that we don’t have time to misbehave.

Which of the following statements best reveals the absurdity of the above argument?

A.    It is a personal account and therefore offers a narrow point of view.

B.    The author attends the high school in question and is therefore biased, making her argument invalid.

C.    Since the author is admittedly enrolled in all upper-level courses, she is only aware of the behavior of the most advanced students at her school.

D.   The author bases her argument only on her own behavior, not the behavior of her classmates.

E.    The author is clearly misrepresenting the truth since all high schools have some sort of behavior problem.

The author of this passage argues that since none of the students in her advanced classes at Gateview High School misbehave, then there is not a behavior problem at the school. Because this student has classes with only the top-performing students at the school, she is not in the position to make such a broad statement about Gateview’s overall student population. Therefore, C is the correct choice.

Let’s look at the other choices:

A. It is a personal account and therefore offers a narrow point of view.

This answer is very similar to the correct answer and is therefore, tempting. However, a close examination of the wording reveals its inaccuracy. The use of the word “therefore” in the answer selection states that the point of view in the argument is too narrow because it is a personal account. This is not true. Since the author of the passage attends the high school, her personal account would be valid if she attended regular classes at the school. It is her enrollment in only upper level classes that limits her perspective, not the fact that her argument is a personal account.

B. The author attends the high school in question and is therefore biased, making her argument invalid.

Although it is true that the author may be biased toward the school since she is a student there, there is nothing in the passage itself that implies bias, and it is not the major flaw of the argument.

D. The author bases her argument only on her own behavior, not the behavior of her classmates.

We can immediately eliminate this answer choice on the basis that it is simply not true. Although the author does reference her own behavior, she also talks about the behavior of her classmates.

E. The author is clearly misrepresenting the truth since all high schools have some sort of behavior problem

A careful reader will have no problem eliminating this answer either since it is an opinion statement, is not based on the argument, and makes a gross over-generalization—that  “all high schools” have behavior problems.

Ø  More Practice from the GMAT**®** Review 13****th Edition: Questions 2, 8, 20, 51, 100

Inference Questions

There will be a few inference questions on the test. These questions do not require you to distinguish the evidence from the conclusion when you read the passage. In fact, the entire passage consists of evidence and your task is to select a proper conclusion.

Inference questions are often presented in one of the following ways:

•       Which of the following conclusions can be most properly drawn from the information above?

•       Which of the following most logically completes the passage below?

•       If the statements above are true, which of the following must be true?

•       The statements, if true, best support which of the following as a conclusion?

Let’s look at a few sample questions.

When people experiment with hard drugs such as cocaine or heroin, there is no certainty that they have also tried softer drugs such as marijuana. There are a great many factors that could lead a person to experiment with hard drugs. Nevertheless, many opponents of legalizing marijuana claim that it is a gateway drug, one that leads its users to try progressively more dangerous substances.

If the statements above are true, which of the following must be true?

A.    *If marijuana were legalized, drug use in general would become a bigger problem. *

B.    If a person abstains from marijuana use, he or she will not try other, more serious drugs either.

C.    Preventing a young person from trying marijuana increases the likelihood that he’ll try other drugs.

D.   A decrease in marijuana use would cause a decline in other types of drug use as well.

E.    Marijuana is sometimes inaccurately determined to be the cause of hard drug use.

The main idea of the passage is that marijuana use contributes to the likelihood that a person will try other, more serious drugs. It does not argue that this is the only contributing factor, however. This distinction is important and can help us in eliminating some of the wrong answers. Let's take a look:

A. If marijuana were legalized, drug use in general would become a bigger problem.

Although the passage does indicate that some people believe marijuana use leads people to try other drugs, the passage also indicates that this is not always the case. There are too many factors that the passage does not discuss to be able to draw such a conclusion.

B. If a person abstains from marijuana use, he or she will not try other, more serious drugs either.

This answer choice is also too extreme. Although the author implies that abstaining from marijuana can decrease the likelihood that a person will try other drugs, he does not rule out the possibility of other contributing factors that may cause a person to try other drugs.

C. Preventing a young person from trying marijuana increases the likelihood that he will try other drugs.

This option was probably the first one you eliminated because it directly contradicts the argument offered in the passage. The passage implies that preventing a person from trying marijuana will decrease, not increase, the likelihood that he will try other drugs.

D. A decrease in marijuana use would cause a decline in other types of drug use as well.

This statement is too broad a generalization to make from the argument presented in the passage. As we already mentioned, the author does not rule out the possibility of other factors that may contribute to drug use; therefore, we cannot state that a decrease in marijuana use would necessarily decrease drug use in general because we cannot control these other factors.

E. Marijuana is sometimes inaccurately determined to be the cause of hard drug use.

The passage says that there are many causes of hard drug use, and that prior marijuana use is not a certainty despite the tendency of some people to believe it is. Therefore, this is a valid conclusion.

Here's another inference question:

Preschool children are the targets of most of the advertisements run during morning and daytime television. In fact, some of the most successful ad campaigns are those directed towards small children. Corporations spend millions of dollars per year creating commercials that appeal to children under the age of five. More often than not, this is money well-spent and contributes to mass profits for these companies.

If the statements in the passage above are true, which of the following must also be true?

A. When children see an item advertised on a commercial that immediately precedes their favorite television show, they are much more likely to express a desire for this item.

B. Childhood obesity rates will rise in proportion with the number of fast food commercials run during morning and prime time hours.

C. Children who are easily influenced by television commercials will make poor financial decisions as adults.

D. Parents and other caregivers sometimes give in to children's demands for items advertised on television.

E. Parents will be able to save more money per month if they limit the amount of television their children are allowed to watch during morning and prime time hours.

The author of this passage makes the case that commercials targeted towards preschool children are very successful and result in big profits for corporations. Since children of this age are not capable of earning money or going to the store themselves to purchase items they've seen on television, it stands to reason that parents and caregivers must be giving in to their children's demands. Therefore, D is the correct answer.

Now, let's examine the other choices and use some of our strategies to eliminate them:

A. When children see an item advertised on a commercial that immediately precedes their favorite television show, they are much more likely to express a desire for this item.

This choice is too specific to be the correct answer. Although the argument does say that children are influenced by commercials played during certain hours, it says nothing of the timing of certain commercials in relation to a child's favorite shows. In addition, to say the commercials that precede are more effective is unsupported. They could be during or after.

B. Childhood obesity rates will rise in proportion with the number of fast food commercials run during morning and prime time hours.

Remember, one of our strategies is to eliminate answer selections that go beyond the scope of the text; this is one of those choices. The passage says nothing of childhood obesity rates and does not provide enough information related to fast food commercials or nutritional values in order to make this inference.

C. Children who are easily influenced by television commercials will make poor financial decisions as adults.

Again, this selection goes way beyond the scope of the passage and can be eliminated immediately. Remember, even if you agree with the answer choice and believe it to be true, do not let this influence your choice. Stick to the text!

E. Parents will be able to save more money per month if they limit the amount of television their children are allowed to watch during morning and prime time hours.

This choice is much too broad to be the correct answer. Although it is loosely tied to the subject of the argument, it is not well-supported by the passage. There are way too many other factors influencing a family's ability to save money to make such a claim. It also assumes that all parents give in to their children's demands for items they've seen on television, and the strategies we've learned tell us to eliminate such over-generalizations.

More Practice from the GMAT® Review 13th Edition: Questions 26, 38, 66, 91, 103

Explanation Questions

These questions are completely different from the other types of questions for the very reason that they present no argument. Instead, the passage, which usually contains the argument, will describe a situation with two or more contradictory facts. Answering the question means explaining how the two contradictory facts can actually be true. You will find that incorrect answer choices typically touch upon only one fact, make the decision even more ambiguous, make a pointless comparison, or fail to address the scope.

Explanation questions are often presented in one of the following ways:

• Which of the following, if true, would most help to explain…

• Which of the following, if true, does the most to explain…

Here's an example:

Parental education initiatives and social programs designed to boost a child's chances for proper brain development are at an all-time high. Even so, there are more cases of children with learning disabilities today than there were twenty years ago.

Which of the following, if true, contributes most to an explanation for the apparent contradiction noted above?

A. Brain disorders among the elderly are also on the rise.

B. Teachers are better equipped to handle children with learning disabilities today than they were twenty years ago.

C. Increased awareness of learning disabilities has led to an increase in diagnosed cases.

D. Children with learning disabilities have more opportunities than ever before.

E. Parents let their kids watch too much TV these days.

The passage introduces the contradiction that despite increased efforts to promote proper brain development amongst children, there are still many more children with learning disabilities today than there were twenty years ago. Choice C is the only answer that explains this contradiction in a logical way, noting that along with prevention efforts, there have also been campaigns to increase awareness of learning disabilities, which has no doubt led to an increase in diagnosed cases.

Now, let's look at the other choices and analyze why they are wrong:

A. Brain disorders among the elderly are also on the rise.

This answer choice goes outside the scope of the issue presented in the passage. We are not concerned with the rise in brain disorders amongst the elderly, unless it somehow explains the rise in learning disabilities in children, which it does not, at least not by this answer choice.

B. Teachers are better equipped to handle children with learning disabilities today than they were twenty years ago.

This statement, although it may be true and is certainly interesting, is also irrelevant. The fact that teachers are better prepared to teach learning-disabled children does nothing to explain the rise in prevalence.

D. Children with learning disabilities have more opportunities than ever before.

This option is very similar to the previous one, a clue that neither of them are right, since you can only pick one. Again, the statement may be true, but it does not explain why learning disabilities have become more common.

E. Parents let their kids watch too much TV these days.

This choice is very tempting since it's easy to assume that watching too much TV can cause learning disabilities. Even if this assumption could be proven, it is not stated in the answer choice. Remember not to assume too much, especially when choosing amongst possible answers. The use of the phrase "too much" is also vague and subjective, making this option much too general to be the correct choice.

Let's look at another explanation question:

Seventy-five percent of customers surveyed on Food-Mart's coupon site reported that they would only purchase a full-price item at Food-Mart if they also had a coupon for that item. However, on an average day, Food-Mart sells more non-sale items without coupons than with coupons.

If the above statements are true, which of the following best explains the apparent discrepancy?

A. The people surveyed on Food-Mart's coupon site are not representative of the average Food-Mart customer.

B. Food-Mart only redeems coupons at face-value whereas their competitor doubles coupons on Wednesdays.

C. The local economy has experienced a setback and Food-Mart's overall sales have declined slightly.

D. More sale items are purchased on an average day at Food-Mart than non-sale items.

E. Customers who spend more than $100 per shopping trip are less likely to use coupons than those spending less than $100.

The author makes the argument that a paradox exists between the results of the survey on Food-Mart's coupon site and the actual amount of coupons used on non-sale items. The critical issue that he fails to address is that the customers who would take a survey on the coupon site are much more likely to use coupons than the average customer. Therefore, the survey is not a reliable indicator of overall coupon usage. This is the missing link that explains the discrepancy. Thus, A is the correct answer.

Now let's examine the wrong answers:

B. Food-Mart only redeems coupons at face-value whereas their competitor doubles coupons on Wednesdays.

This is a classic case of the kind of faulty comparisons often found in incorrect answer choices. The passage speaks only of coupons used at Food-Mart; therefore, the information about Food-Mart's competitor is irrelevant.

C. The local economy has experienced a setback and Food-Mart's overall sales have declined slightly.

You probably eliminated this choice first since it not only fails to explain the discrepancy, it complicates it further. If the economy is faltering, it would stand to reason that more people would use coupons, especially on non-sale items.

D. More sale items are purchased on an average day at Food-Mart than non-sale items.

This answer selection goes beyond the scope of the argument. The issue here is how many non-sale items are purchased with and without coupons. A comparison between the sales of full-price and sale items is irrelevant.

E. Customers who spend more than $100 per shopping trip are less likely to use coupons than those spending less than $100.

Since this selection fails to mention the major focus of the argument—coupon usage as it pertains to non-sale items—it cannot possibly explain the apparent paradox.

More Practice from the GMAT® Review 13th Edition: Questions: 17, 24, 57, 61, 94

Evaluate Questions

The last type of question that you will find on the GMAT is an evaluate question. These will contain evidence and a conclusion, but the task you have to complete can vary a lot from question to question, Sometimes you will need to analyze the evidence for flaws or assumptions, sometimes you will need to think about what is missing from the argument, and sometimes you will need to analyze the structure of the argument. It is important that you read the question carefully and understand the task before you jump into the answers.

Evaluate questions are often presented in one of the following ways:

• In evaluating the argument, it would be most useful to…

• Which of the following would it be most useful to determine in order to evaluate the argument?

• For purposes of evaluating the argument, it would be most useful to establish which of the following?

• Which of the following must be studied in order to evaluate the argument presented above?

Here's an example:

For similar food products within a single grocery store, brand names items have always cost more than the generic items have. However, market research indicates that the cost of the ingredients that are used to make brand name and generic items are identical. Therefore, companies that manufacture brand name food products have a greater profit margin than do companies that manufacture generic food products.

In evaluating the argument it would be most useful to compare

A. the average quantity of brand name items compared to generic items over a certain time period

B. labor and equipment costs for the two different types of companies

C. the sale prices of similar food items in other grocery store chains

D. consumer preferences for brand name items over generic items for certain food products

E. the profit margins for brand name and generic household goods

The evidence is that the prices between the two items are different, with brand name prices being higher. Since the cost of ingredients is the same, the author wants you to believe that the difference in price represents profit for the brand name companies. However, there may be other factors that affect profit margins. Answer B brings in some of those other factors. If labor and equipment costs are the same for the two types of companies, then the argument is valid. If the costs differ, then the argument is not valid. Answer B is correct.

Now let's look at the other choices:

A. the average quantity of brand name items compared to generic items over a certain time period

This choice doesn't help with the question. First of all, we're not told if this quantity is quantity produced or quantity sold. Even if we're talking about the quantity sold, we know the brand names sell for more, but we don't know how much the companies are making on each item. So, quantity alone doesn't help us.

C. the sale prices of similar food items in other grocery store chains

This is only marginally related. The premise is about items within a single grocery store. Bringing in other stores complicates the issue.

D. consumer preferences for brand name items over generic items for certain food products

We already know that the brand names sell for more, but knowing that consumers tend to prefer brand names over generic items doesn't help us evaluate the profit margins.

E. the profit margins for brand name and generic household goods

This is a trap answer. It introduces a faulty comparison (household goods vs. food products), and so it does not help us evaluate the argument.

More Practice from the GMAT® Review 13th Edition: Questions 34, 45, 68, 110