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GMAT Critical Reasoning Cheat Sheet: A Proven Strategy From A 99th Percentile Scorer & Tutor (FULL Guide)

We all know that scoring well on GMAT’s Critical Reasoning isn’t a cakewalk. Getting a good score relies on great practice. But for some of us, even after lots of hard work and effort, CR can be a tough nut to crack.

Why is this the case? It’s almost always down to having the wrong approach to practice.

The GMAT is a skills-based test, so you have to learn by doing rather than ‘studying’. So if you’re overwhelming yourself with a bunch of rules and terms and formal logic first, hoping to apply them ‘later’…then that’s the wrong approach. Another common issue? Learning to run before you walk. Jumping straight into timed practice is a recipe for frustration. Instead, slow down. Yes, you’re not going to be perfect. You’ll make mistakes. Including really silly mistakes. This is normal. Focus on accuracy first, and worry about speed later.

Remember, it’s perfect practice that makes perfect. 

In this blog post, we’ll present a simple step-by-step process that’ll help you approach GMAT Critical Reasoning with both simplicity and confidence. No more overwhelm. No more stalled progress. It’s a proven strategy that brings results, fast.

The process was created by Trevor Klee, GMAT tutor and creator of study app 21st Night, who scored in the 99th percentile on the GMAT Verbal. It’s also the exact process he’s taught all his students to help them achieve top scores too. 

At the end of the post you’ll also find a summary of this GMAT Critical Reasoning Cheat Sheet that covers the entire strategy in a nutshell.

How Do I Get Better At Critical Reasoning On The GMAT?

Almost every GMAT Critical Reasoning question is, in essence, an argument. And the good news is that all arguments have consistent, predictable structures. 

By treating everything like an argument that has a decipherable structure, you can quickly build the core critical reasoning skills needed to improve on the GMAT. In fact, once you know how to confidently deconstruct an argument by identifying the conclusion, the reasoning, and any missing links leading us from the reasoning to the conclusion, the question practically solves itself. 

The key to increasing your GMAT critical reasoning score is to master this one process. 

We can’t emphasize enough the importance of having an error log. There’s a great expression in math education that goes something like ‘celebrate your mistakes’. The purpose of this is to reframe how kids perceive making errors in math; from something that’s ‘bad’ into something that actually spearheads learning. The same concept is incredibly useful when applying it to any skill you’re trying to learn. When you maintain an error log and use it to fuel your practice, progress comes quickly.  

So when you attempt a practice question, slow down and actively try to verbalize why you got it right (or wrong). This kind of slowed down, conscious, deliberate practice is critical to achieving the proficiency needed to get a high score. 

(If you need help with making and maintaining error logs for the GMAT, here’s a guide on how to do that with the study app 21st Night.)

How To Break Down Any GMAT Argument 

Take a look at these statements:

i) It’s going to rain today. 

ii) The weather forecast says it might rain today, and the sky is also overcast today. Therefore, it’s going to rain today.

Which one is an argument? 

i) is just a comment about the weather. We don’t know if it’s a fact, an opinion, or an announcement, but it’s not trying to convince you of anything. 

ii) makes the same point as i), but the difference is it’s actually trying to convince you that it’s true, using a specific line of reasoning. Not only does it state that it’s going to rain today, but it also attempts to give you some logical justification for that comment (i.e. the weather forecast, and how the sky looks). 

So an argument contains not only a conclusion (an opinion, prediction, or some kind of comment), but also the reasoning (a set of ideas that attempt to back up the conclusion).

The reasoning given in GMAT questions is often incomplete, however. Bits of the reasoning may be explicitly stated, but there might be other bits that are not stated outright but nevertheless need to be there in order for the argument to make sense. 

Identifying these ‘gaps’ is an important skill for Critical Reasoning. Let’s call them missing links: ideas or assumptions that are not explicitly stated but bridge the gap between the reasoning provided and the conclusion:

In the example given, the argument-maker says that the sky is overcast, but the assumption that an overcast sky signals rain is also hidden in there in order for the conclusion to make sense. And that’s just one missing link. There can be several, such as ‘the weather forecast can be trusted’, and so on.  

As the diagram shows, it’s always good to keep in mind that the reasoning provided in the stimulus, in itself, doesn’t lead to the conclusion. There’s almost always a missing link.

Putting It All Together: The GMAT Critical Reasoning Process 

For any CR question, the first step is really to fully understand the argument presented. 

As we saw earlier, arguments have predictable structures, so we can train ourselves to see every argument as being made up of three parts: the conclusion, reasoning, and missing links. Identifying those parts in that order:

  1. Find the conclusion. This is something we can put ‘therefore’ in front of.
  2. Find the reasoning provided. This is something we can put ‘because’ in front of.
  3. Find the missing link(s). This is something that isn’t stated, but nevertheless needs to be true in order for the conclusion to make sense.

This simple process will help you crush every CR question type, from assumption questions to inference questions to boldface questions. 

Every question type will however call for a slightly varied plan of attack. For example, you should know that inference questions have missing conclusions, assumption questions are all about spotting missing links, and boldface questions are about being hyper-aware of how the overall argument is structured. And so on.   

To show you exactly what all this means, we’ve included five full practice questions below, with step-by-step guidance on how you’d approach them using this strategy.

P.S. For lots more worked examples using this approach, check out Trevor’s book: The GMAT Critical Reasoning Process. It’s got a ton of basic-to-insanely tricky questions with in-depth explanations so you can truly master all the skills you’ll need to ace Critical Reasoning. 

How Do You Solve Strengthen or Weaken Questions in GMAT Critical Reasoning?

Strengthen/weaken questions are ones you’ll frequently come across in Critical Reasoning, and the good news is they’re very straightforward to tackle using our process.

The goal here is to figure out what the missing link is and then hone in on the answer choice that addresses the gap.

For a Strengthen question, we’re looking for information that reinforces the missing link, and for a Weaken question, we look for evidence that discounts it. 

Crucially, what we’re not looking for is information that affects or argues with the reasoning already given—the reasoning needs to be taken as a given. 

Worked example:

First, let’s find the moralist’s conclusion. Remember, this is an opinion, comment, or idea that we can put ‘therefore’ in front of.

Conclusion: “It was not wrong for Jose to predict rain.”

Next, find the moralist’s reasoning—the statements or assertions we can put ‘because’ in front of.

Reasoning: 1) “Lying is wrong.” 2) “Jose had no good reason to believe that his prediction of rain was wrong” (i.e. he wasn’t lying). 

Next, see if you can find any gaps between the reasoning and the conclusion.

Missing link: The moralist’s reasoning is all about lying, but his conclusion isn’t specifically about lying, it’s about Jose being (morally) wrong. Is lying the only reason someone might be wrong in making a prediction? Not necessarily. 

[Quick detour: if you have trouble ‘seeing’ this gap, try switching the stimulus from something banal (predicting rain) to something more emotionally charged (predicting who would die from a disease):

Let’s say Jose made a prediction that no one would die from Disease X. Jose is fairly confident that his prediction is true, so technically he’s not lying. But could he still be morally wrong in making that prediction? If his prediction could have a negative impact on society, for example, by causing people not to take precautions from contracting Disease X, you could make the case that it’s still wrong for him to do that, whether or not he believes he’s telling the truth.]

Now that we understand the argument, and most importantly the missing link, we now need to look for the answer choice that exploits this. In order to weaken the moralist’s argument, we need something that shows you can be wrong without technically lying, for example, if the consequences of your actions negatively impact someone else.

Here are the answer choices:

a) It is also wrong to say things that could ruin someone’s plans if you aren’t positive they are true.

This kind of hits the nail on the head. It says it’s wrong to say some things, even if you’re not telling an outright lie. 

b) Jose’s prediction turned out to be false.

Whether Jose’s prediction was accurate or not isn’t relevant to the argument. 

c) At the time the moralist said this, Jose still could have been right in his prediction.

Same thing as b). 

d) There’s no objective way of proving whether something is wrong.

This doesn’t exploit the missing link. 

e) Even if Jose had a good reason to believe his prediction was wrong, he still would have said it.

This one is arguing with the reasoning provided, which doesn’t weaken the argument in GMAT terms.

The correct answer has to be a).

How Do You Solve Boldface Questions in GMAT Critical Reasoning?

Boldface questions are those that rely on you understanding the purpose of selected statements in the stimulus. 

They’re great because they basically test exactly what we’re training ourselves to do: identifying the structure of the argument—in other words: can you find and differentiate the conclusion, the reasoning, and any missing links?

Worked example:

First, let’s find the conclusion. 

Conclusion: It is a misconception that scientists have calculated that bumblebees are too heavy to fly.

Then, find the reasoning. Why does the argument-maker think this is a misconception?

Reasoning: 1) “Bernoulli’s principles allow for bumblebees to fly just as well as airplanes.” 2) “Any scientist who did the calculations on a bumblebee’s weight and wing strength would have no problem proving that it was possible for a bumblebee to fly.”

Lastly, we can skip figuring out the missing link in this one, since we’ve covered both boldface portions. 

So now we know that the first boldface statement isn’t the conclusion or part of the reasoning, but rather a kind of set-up to the argument. We also know the second boldface statement is part of the reasoning.

This helps us narrow down on the answer choices. 

a) The first is a claim whose implications are at issue in the argument; the second is reasoning that supports the main conclusion of the argument.

This fits our understanding of the argument. 

b) The first is the main conclusion of the argument; the second is reasoning that supports the main conclusion of the argument.

The first statement isn’t the conclusion, so we can dismiss this. 

c) The first is a claim that the argument denies; the second is reasoning that supports the main conclusion of the argument.

The argument-maker doesn’t deny that a scientist may have joked about it, so the first part of this answer choice is wrong. 

d) The first is the main conclusion of the argument; the second is a premise that supports the conclusion of the argument.

Same thing as b). 

e) The first is a premise that supports the conclusion of the argument; the second is the main conclusion of the argument.

Both parts of this answer choice are wrong, so we can easily dismiss this.

The correct answer has to be a).

How Do You Solve Deductions and Inference Questions in GMAT Critical Reasoning?

A deduction or inference is a statement you can make based on a given line of reasoning. In other words, they’re conclusions.

A common trap in this question type is going beyond the information that’s provided. It may be useful to think of an inference as the ‘very next step’ you can take based on the information given. This will help you avoid making huge leaping conclusions. 

Worked example:

Let’s closely examine the information given to us in the stimulus. 

The doctor states that 1) his hypothesis on the source of the patient’s rash has not been confirmed by the lab analysis. He also states that 2) the lab analysis was poorly performed. These statements make up his reasoning. 

If 1) is true and 2) is also true, what else must be true? That’s your inference. 

If the lab analysis wasn’t properly done, that means that the lab results might be inaccurate. And if the lab results might be inaccurate, that means you can’t really use them to judge the doctor’s hypothesis. 

[Quick tip: Try putting it in ‘therefore’ form to help you cement that conclusion: Therefore, the lab analysis cannot be used to evaluate the doctor’s hypothesis.]

The correct answer will identify this as the most supported conclusion. Incorrect answer choices, on the other hand, may make leaping statements or just be outright irrelevant. 

a) The patient is incorrect about the doctor’s hypothesis.

Whether the patient is actually correct or incorrect goes beyond the line of reasoning provided. 

b) The lab analysis, even if it had been performed correctly, would not have been enough to make conclusive statements about the hypothesis.

The doctor doesn’t say anything about the particular kind of lab analysis being sufficient or not, so this is a pretty big leap. 

c) If the lab results had been performed correctly, the doctor’s hypothesis would have been proved.

The doctor doesn’t say anything to imply this at all. Another big leap.

d) The lab analysis, as it is, actually confirms the doctor’s hypothesis.

This is arguing with the reasoning provided. In the GMAT, we always have to accept the reasoning that’s provided. 

e) The poor quality of the lab analysis renders it worthless.

Bingo. This is the answer choice that hones in on the only safe conclusion we can make: that the lab results aren’t good enough to do anything worthwhile with it.

The correct answer has to be e).

How Do You Solve Explain or Resolve Questions in GMAT Critical Reasoning?

‘Explain or resolve’ questions are also called ‘paradox’ questions. They give you two pieces of information that, on first glance, seem to contradict or conflict with each other and ask you to resolve the paradox (in other words, explain the contradiction). 

These questions hinge on you finding the missing link.

The aim is to identify what should be our conclusion from the stimulus, then analyze the reasoning that’s provided. Finally, we need to figure out what the missing link is that could lead the reasoning to the conclusion. 

Worked example:

First, find the piece of information that has to be the conclusion we’re looking to reach. 

In this case, it’s: The New York Art Competition values originality.

Then we identify the piece of information that’s supposed to be our reasoning: This year’s grand prize was influenced by last year’s prize.

Now, let’s figure out the missing link. To do this, you’ll need to pinpoint exactly why the two pieces of information are seemingly at odds with each other. Well, if the prize was influenced by another painting, then that doesn’t seem to be very original isn’t it? Well then how come it won? That’s where the missing link should lie. It should be information that explains why this year’s grand prize still won, despite it being influenced. 

Remember, we’re looking for something that explains the contradiction without actually disputing the reasoning provided. 

Take note that this question asks you to identify the one choice that DOESN’T resolve the paradox. So you’re looking for something that might add to the paradox (rather than eliminate it), or something that doesn’t do anything to explain why the apparent contradiction exists. 

a) art critics often enjoy paintings that can appear innovative while showing their influences

This states that critics like paintings that can look original while still revealing they have been influenced. This could very well be a missing link as it explains how such a painting could’ve won. 

b) Dionysus won a grand prize so long ago that the art world at large has forgotten about it

If people have forgotten about the original painting, it makes sense that this year’s prize still looked original in the judges’ eyes. This could be a missing link. 

c) it’s easier to create a painting if it’s within an established tradition

This one doesn’t address the contradiction. Even if it’s easier to make such a painting, how does that explain why it won for its apparent originality? It doesn’t. 

d) while Apollo was influenced by Dionysus, it was sufficiently different in its details to still be original

This offers a possible explanation on how the painting could’ve still looked original while being influenced. 

e) Apollo displayed technical skill far beyond any other painting in the competition

Again, this offers a possible explanation on how the painting could’ve still looked original while being influenced. 

The correct answer has to be c).

How Do You Solve Assumption Questions in GMAT Critical Reasoning?

Assumption questions, despite being the hardest for some GMAT test-takers, can actually become very straightforward to solve using our process.

Think of assumptions as basically being code words for ‘missing links’. The goal is to find the missing link that allows us to go from the reasoning to the conclusion. 

If you’re just starting out with this question type, it’s good to keep in mind that sometimes these missing links can seem so elusive or well hidden. Other times they’re so obvious you might roll your eyes. In any case, don’t worry—with practice, they become a lot easier to figure out! 

Worked example:

You know the drill by now. First, let’s find the conclusion.

Conclusion: Doug’s Farm Stand should refund the shopper’s potatoes. 

Then, find the reasoning.

Reasoning: 1) The potatoes bought from Doug’s Farm Stand are now rotten. 2) The grocery store provides a refund for rotten potatoes if they’re rotten by the time they get home. 

The missing link here is that the grocery store only provides a refund for the rotten potatoes, if they’re rotten by the time the shopper gets home. If you bought potatoes from them but they rot in a week, they don’t give out refunds. 

So the potatoes from Doug’s Farm Stand that are rotten now must have been rotten by the time the shopper got home. 

This isn’t explicitly written out in the stimulus, which is exactly why it’s an assumption. Notice how the assumption clearly ties the blame to the service provider (Doug’s Farm Stand) and not some other factor (how the shopper stored the potatoes post-purchase, for example). 

[Quick detour: If you have trouble training yourself to ‘see’ the missing link, try substituting the stimulus for a more dramatic or interesting scenario, like we did in a previous question. Here’s one:

Let’s say someone wants her hairdresser to give her a refund. Here’s her reasoning:

Conclusion:  My hairdresser needs to give me a refund. 

Reasoning: 1) My haircut sucks, 2) Other hairdressers give out refunds when they botch their clients’ hair. 

Missing link: My haircut was done by my hairdresser. 

It’s kind of obvious, but we absolutely need to assume the link is there even though it’s not explicitly stated. If she did the haircut herself, then the conclusion just doesn’t hold up. Like in our question, the missing link ties the responsibility of the bad haircut—or the rotten potatoes—to the service provider and not to any other factor.)

Now let’s look through the answer choices.  

a) Doug’s Farm Stand should not have sold the potatoes if they knew they were rotten.

The shopper doesn’t mention anything about whether the potatoes should have been sold in the first place. So this is irrelevant. 

b) The potatoes from the grocery store go through the same quality control process as the

potatoes from Doug’s Farm Stand.

Again, the shopper’s argument doesn’t rely on quality control. So this is irrelevant. 

c) Vegetable sellers should refund money that’s spent on indelible products.

The shopper already mentions this, so it’s not an unstated assumption. 

d) The potatoes were rotten when the shopper came home from Doug’s Farm Stand.

This nicely zeroes in on our missing link. It ties up why the reasoning provided leads to the conclusion. 

e) Doug’s Farm Stand occasionally sells rotten potatoes.

This doesn’t connect the shopper’s reasoning to the conclusion the way d) does. 

The correct answer has to be d).

If you’ve made your way through this entire guide, congratulations, you now have a pretty strong foundation for CR! In the next section, you’ll find a cheat sheet that squeezes everything you’ve read into a handy summary. Happy practicing and good luck!

GMAT Critical Reasoning Cheat Sheet Summary + More Resources

Structure Of An Argument

Conclusion – an idea or opinion we can put ‘therefore’ in front of.

Reasoning – a set of ideas put forward to support the conclusion—something we can put ‘because’ in front of.

Missing link – something that’s not explicitly said by the argument-maker, but is assumed to be true for the conclusion to make sense.

Plan of Attack by GMAT Critical Reasoning Question Type

Critical Reasoning Question TypePlan of AttackExample Questions
Strengthen/WeakenIdentify the conclusion and reasoning. 
Find the missing link(s). 
Choose the answer choice that strengthens or weakens the link.
Which of the following, if true, would most weaken the argument?
Which of the following, if true, most strengthens the author’s argument?
BoldfaceFind the conclusion, reasoning, and missing link(s). 
Figure out how each sentence contributes to the overall argument structure. 
The two statements in ​boldface​ play which of the following roles in the argument?
Deductions and Inferences Identify the reasoning.
Identify the missing link(s) – if relevant.
Combine the pieces of reasoning to form the safest conclusion. 
Which of the following is most supported by the author’s statements?
Which of the following most reasonably completes the argument?
Explain or Resolve QuestionsIdentify the implied conclusion. 
Identify the reasoning already provided.
Figure out the missing link that can explain the contradiction. 
Which of the following, if true, would most help to resolve the paradox?
AssumptionIdentify the conclusion and reasoning. 
Find the missing link(s). 
Choose the answer choice that best addresses this gap. 
The author’s conclusion requires which of the following assumptions?

How To Practice The Right Way

  1. Build your basic critical reasoning skills by first trying out questions from each question type, untimed.
  2. For each question, reflect on why you got it right (or wrong). Mastering the question means you can explain (out loud or in writing) why each answer choice is correct/incorrect.
  3. Make an error log. Track your errors and save your explanations (you can use a study app such as 21st Night).
  4. Review those questions periodically to refresh your memory.
  5. To speed up your skills, try out official practice tests and questions, timed. 
  6. Once again, log your errors and explanations and review them periodically.

More Resources

Want even more guidance with great step-by-step worked examples? Check out the book The GMAT Critical Reasoning Process. Written by GMAT tutor and top GMAT scorer Trevor Klee, you’ll learn how to solve every single kind of CR question type using this process with tons of practice questions. Available for instant download, so you can start practicing right away!

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