Critical Reasoning – the “Best” Wrong Answer
Stop me when this story sounds familiar:
1) You read a CR argument.
2) You read the answer choices.
3) You easily eliminate 3 of them.
4) You re-read the remaining 2.
5) You’re not sure which is correct.
6) You re-read the argument.
7) Repeat Steps 4)–6).
You’re not in bad company – this is one of the most common problems all of us run into on Critical Reasoning. If you think this happens to you all too often, it’s time to learn how to break the cycle!
Just to be clear, the issues I’ll discuss in this article are not ones you should be worried about unless you already have your fundamental CR Process in place. Here’s a quick overview for those of you who may not know what I mean:
Read the Question Prompt, Identify the Question Type.
There are several major CR question types. You should be familiar with them and be able to recognize them quickly.
Deconstruct the Argument.
Focus on finding the Conclusion, then figure out how the other parts of the argument relate to that conclusion.
Restate the Goal.
Try to rephrase the question in a way that ties it to the specifics of the argument you just read.
Work From Wrong to Right.
Generally speaking, it’s process of elimination from here on out!
In step (iv), I don’t mean to say that CR should always be strictly a process of elimination (the way SC should be). Every now and then you’ll see a CR answer choice that was exactly what you were looking for, and it’s OK to run with that. But generally speaking, you should try eliminating wrong choices rather than justifying correct ones – much more on this later! Anyway, the point is that most of this article deals with the final stage of step (iv), so please make sure you’re following the full process before you even worry about these more advanced techniques.
The simple truth here is that every CR problem ever written has 4 wrong answers. This idea that 3 answers can easily be eliminated, leaving us with a right answer and a very tempting wrong answer, is sometimes called the “3+2 Rule”. Just to be clear, I don’t entirely agree with the notion that every CR question has 3 easily-eliminated answers – some CR have 2 or more very difficult wrong answers! But more often than not we see one wrong answer that is just more tempting than the other 3. This is backed up not only by my own anecdotal evidence, but also by actual data! The distribution of wrong answer choices on CR problems from the OG is just about never uniform; rather, there is typically a mode on one particular incorrect answer.
Let’s take a look at one specific problem that nicely exhibits the 3+2 Rule. This is Problem #113 from the Official Guide, 13th ed.
113) The average hourly wage of television assemblers in Vernland has long been significantly lower than that in neighboring Borodia. Since Borodia dropped all tariffs on Vernlandian televisions three years ago, the number of televisions sold annually in Borodia has not changed. However, recent statistics show a drop in the number of television assemblers in Borodia. Therefore, updated trade statistics will probably indicate that the number of televisions Borodia imports annually from Vernland has increased.
Which of the following is an assumptions on which the argument depends?
(A) The number of television assemblers in Vernland has increased by at least as much as the number of television assemblers in Borodia has decreased.
(B) Televisions assembled in Vernland have features that televisions assembled in Borodia do not have.
(C) The average number of hours it takes a Bordian television assembler to assemble a television has not decreased significantly during the past three years.
(D) The number of televisions assembled annually in Vernland has increased significantly during the past three years.
(E) The difference between the hourly wage of television assemblers in Vernland and the hourly wage of television assemblers in Borodia is likely to decrease in the next few years.
As always, let’s begin by running through our 4-step process for CR.(1) Identify the Question Type.
This is a Find the Assumption question.(2) Deconstruct the Argument.
The Conclusion here is that updated trade stats will (probably) show an increase in televisions going to Borodia from Vernland. The Premise is basically while Borodia still consumes the same number of TVs, they now have fewer television assemblers.(3) Pause and Restate the Goal.
We’re looking for something the argument needs to function correctly.(4) Work from Wrong to Right.
Let’s run through those answer choices:
(A) There’s no need to assume a 1-for-1 match here, or even that Vernland have increased its pool of TV assemblers. Quick Elimination.
(B) There’s definitely no need to make assumption about TV features. Quick Elimination.
(C) Seems a little strange, perhaps, but notice that this choice says something strange won’t happen, which is a very common type of assumption. Leave in for now.
(D) Seems relevant. Leave in for now.
(E) This point is little tricky, but while the Conclusion here appears to be a prediction about the future (“statistics will indicate”), it’s actually about the recent past – the decrease in Borodian TV assemblers has already happened, we’re just waiting for some stats on the number of imported TV. Consequently, we don’t need to assume anything about what will happen in the future! Quick Elimination.
There we have it – 3 choices out for pretty easy reasons, and two tricky answers remain. So, how do we handle this? Running into this problem often causes students to conclude “I am bad at CR.” But the problem actually stems from the fact that we, as human, are inherently good at something:
We are all awesome at justifying arguments to ourselves!
Just think about the last time you procrastinated on something important. There was a lot of evidence that you shouldn’t be procrastinating, but convincing yourself that it was OK to put off your project was probably none too difficult (at least if you’re anything like me!) – I’ll just send a few more emails first; Right after this episode of The Colbert Report I’ll buckle down; It wouldn’t be so tragic if this got finished tomorrow; etc., etc.) We can convince ourselves of just about any bad idea we need to, because we’re all good at arguing with other people and not so good at questioning our own arguments!
What does this have to do with the 3+2 Principle on CR? If you’re down to two answer choices and try to justify the correct answer, you will almost certainly mount a decent argument for either choice and find yourself running around in circles. Instead, our M.O. should be to isolate a serious flaw with one of the two remaining choices. Once you’ve spotted such a flaw, the answer that has it is out and the last answer left standing is it – no need to justify!
Getting back to that example (OG13 CR #113), let’s remind ourselves what assumptions really do. Consider the following (not so great) argument:
“All kids like ice cream, therefore Joey likes ice cream.”
Of course, you’re all thinking the same question: “What if Joey is all grown up!?” It’s a huge flaw in the argument, which just means that this argument has an assumption: “Joey is a kid.” With the assumption, the argument actually works just fine. (Side note: you might disagree with the statement “all kids like ice cream” but since it’s actually printed it counts as a premise, and on the GMAT we’re not in the game of doubting premises!)
On the other hand, what happens if we take the opposite assumption: “Joey is not a kid
”. What happens to the argument? It completely falls apart!
So if we’re down to 2 remaining choices on a Find the Assumption problem, we can always try looking at the opposites of the choices. Let’s call this the Negation Test
– just negate the two remaining choices and the correct choice, once negated, should destroy the argument!
Try it out with (C) and (D) on #113:
(not C) The average number of hours it takes a Bordian television assembler to assemble a television has
decreased significantly during the past three years.
(not D) The number of televisions assembled annually in Vernland has not
increased significantly during the past three years.
Notice that (not D) doesn’t really hurt our argument. So what if the number of Vernlandian assemblers hasn’t increased significantly? They could still very well be exporting a lot of TVs to Borodia, so the conclusion hasn’t been weakened.
That’s all we need to confidently go with (C), but for completeness let’s think about what (not C) does to our argument. If Borodian TV assemblers can crank out many more TVs per hour than what they could previously produce, then a decrease in the number of assemblers definitely does not mean that we need to import more TVs from Vernland – the remaining TV assemblers are now super-efficient and making all the TVs Borodians could ever watch! (not C) completely destroys this argument, so (C) is the correct answer!
This example leads nicely to my main point. To effectively deal with 3+2 Rule problems you must
develop an “out” for every different CR question type!
The goal is to be prepared in advance for whatever the test might throw your way, so you don’t have to think these difficult issues through “in the moment.” The Negation Test is a great one for Find the Assumption questions. Here’s a short list of techniques I use for some other question types.Describe the Role.
These are those fun “two boldfaced” question where the correct answer describes the role played by each of the two statements. Always start by breaking the overall argument down in Conclusion, Premise, Counterpoint, and Background. If you get stuck between two choices though, it’s often helpful to think whether each bold statement is Fact or Opinion.
(Examples: OG13 CR #63, #76)Evaluate the Conclusion.
These questions are the ones that actually have question as answer choices! The prompt usually reads something along the lines of “the answer to which of the following questions would be most useful in evaluating ...” If you’re down to two choices here, try to actually Answer the Question
different ways! For the correct choice, different answers to the question should have dramatically different implications for the conclusion you are evaluating. (Examples: OG13 CR #72, #110)Draw a Conclusion.
Here, I think it’s most helpful to go into the problem already knowing the most common wrong answer types. You should already know to avoid the Real-World Conclusion
and stick as closely as possible to the language of the argument. But I find that many of the trickiest wrong answers here actually lift language from the argument but then Mismatch
that language. (Example: OG12
CR #70)Major Takeaways:
(1) Once you’re down to 2 answers, don’t try to decide which one you like more.
(2) Instead, focus on finding which one you like less, by which we mean find an unforgivable flaw in one of the choices.
(3) Learn and practice specific outs for each different CR question type.
(4) Rule the CR Universe.What’s your take?
Let me know if the comments section what you think of all this! In particular,
• Have these techniques helped on any particular problems?
• Are there 3+2 Principle problems that aren’t helped by these ideas?
• Do you have any other tricks or outs for these scenarios?
These are some of the most difficult situations we find ourselves in on CR, so I’d love to see this article generate some good conversation (and perhaps even a few arguments)!
Mark Sullivan | Manhattan GMAT Instructor | Seattle, WA
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