How to Read Tough Science Passages
In the past, we’ve done some one-off review of parts of RC passages, but this time I’ve got a full one for you. In this article, we’ll look at how to get through this thing (and what to avoid). Next week, we’ll do a question or two.
I chose this passage from the free set of questions that comes with GMATPrep (that is, it doesn’t actually show up in the practice CAT itself). It’s a longer passage, so give yourself approximately three minutes total to get through.
The Passage
A meteor stream is composed of dust particles that have been ejected from a parent comet at a variety of velocities. These particles follow the same orbit as the parent comet, but due to their differing velocities they slowly gain or fall behind the disintegrating comet until a shroud of dust surrounds the entire cometary orbit. Astronomers have hypothesized that a meteor stream should broaden with time as the dust particles’ individual orbits are perturbed by planetary gravitational fields. A recent computer-modeling experiment tested this hypothesis by tracking the influence of planetary gravitation over a projected 5,000-year period on the positions of a group of hypothetical dust particles. In the model, the particles were randomly distributed throughout a computer simulation of the orbit of an actual meteor stream, the Geminid. The reseNavigator found, as expected, that the computer-model stream broadened with time. Conventional theories, however, predicted that the distribution of particles would be increasingly dense toward the center of a meteor stream. Surprisingly, the computer-model meteor stream gradually came to resemble a thick-walled, hollow pipe.
Whenever the Earth passes through a meteor stream, a meteor shower occurs. Moving at a little over 1,500,000 miles per day around its orbit, the Earth would take, on average, just over a day to cross the hollow, computer-model Geminid stream if the stream were 5,000 years old. Two brief periods of peak meteor activity during the shower would be observed, one as the Earth entered the thick-walled pipe and one as it exited. There is no reason why the Earth should always pass through the stream’s exact center, so the time interval between the two bursts of activity would vary from one year to the next.
Has the predicted twin-peaked activity been observed for the actual yearly Geminid meteor shower? The Geminid data between 1970 and 1979 show just such a bifurcation, a secondary burst of meteor activity being clearly visible at an average of 19 hours (1,200,000 miles) after the first burst. The time intervals between the bursts suggest the actual Geminid stream is about 3,000 years old.
Here’s how to read
When you’re reading an RC passage, think about:
(1) What words or parts of the sentence are so complex that I’m going to ignore them for now?
(2) When can I stop reading and start skimming?
(3) When do I have to start paying close attention again?
Below, I go through each paragraph, noting various things. Normal text means: I did read this but didn’t pay extra attention to it. Boldface text really stood out for me: my brain perked up and paid attention.
Games People Play…Or Don’t
Many a true word is said in jest.—I don’t know, but I heard it from my mother.
I think that Critical Reasoning is my favorite part of the exam because it is the purest of the pure. I’ve written before that the GMAT is an aptitude test rather than a knowledge test. On the simplest level, in both the quant and the verbal, the exam tests a logic system: be specific, don’t assume, and don’t rationalize. Nowhere is this more true than in Critical Reasoning—there is no mathematical foundation work nor are there grammar rules. As Gertrude Stein used to say, There is no there, there. Of course, she was talking about Oakland. . .fill in your own joke. When I’m being* mean to students, I say, If you know what all the words mean, you should get them all right.
But students don’t get them all right. Even those who know what all the words mean. Why is that? Because people think. They assume, they rationalize, and they inject opinions. Why is this bad? Because it’s a game. Critical Reasoning doesn’t take place in reality. Here’s an analogy I thought up all by myself, so it isn’t in the Strategy Guide: Critical Reasoning bears the same relationship to reality that Monopoly does. When you play Monopoly, you don’t think about how reasonable free parking or building hotels is, you exploit the rules. It’s the same thing. A lot of OG arguments involve medical issues, but you hardly ever care whether people live or die because that’s usually not the conclusion. Play the game.
As a by the way, if students struggle with the CR, it’s often half of their trouble in the quant. Folks are not specific; they read the question or the given incorrectly. And they don’t recognize the types and patterns. In other words, they don’t play that game. However, folks fail to notice these mistakes because they are too consumed with worry about their math foundations. Conversely, engineers with strong foundations also suffer here, especially in the DS because they try to use brute mathematical force instead of playing the game. It is a behavioral problem. People don’t do; they think. Don’t think—much like in life, it only gets you into trouble.
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Want a 750+? Do This Critical Reasoning Question in Less Than 60 Seconds.
Recently, I published an article challenging those going for a 750+ to answer a certain Quant question in 30 seconds. I received a lot of positive feedback about that article—and requests for more of the same.
I’m happy to oblige: here’s a GMATPrep CR problem. The normal timeframe is about 2 minutes—but if you’re going for a 750+, you’d need to be able to answer something like this much more quickly. Read more
What’s Parallel to What? Parallelism and Meaning in GMATPrep
The first time I read the original sentence in the below SC problem, I thought to myself: wait, what? What are you actually trying to say? I knew immediately that this would be a good one to discuss with all of you.
Let’s try it out (1 minute 15 seconds) and then we’ll dive in. This question is from the free problem set included in the new GMATPrep 2.0 version of the software.
* Displays of the aurora borealis, or northern lights, can heat the atmosphere over the arctic enough to affect the trajectories of ballistic missiles, induce electric currents that can cause blackouts in some areas and corrosion in north-south pipelines.
(A) to affect the trajectories of ballistic missiles, induce
(B) that the trajectories of ballistic missiles are affected, induce
(C) that it affects the trajectories of ballistic missiles, induces
(D) that the trajectories of ballistic missiles are affected and induces
(E) to affect the trajectories of ballistic missiles and induce
This was my thought process as I read that first sentence:
Comparisons and Parallelism in GMATPrep
Last time, we took a look at a Comparisons problem; in today’s article, we’re going to examine another one. This question is from the free problem set included in the new GMATPrep 2.0 version of the software. Try it out (1 minute 15 seconds) and then we’ll talk about it!
* In Holland, a larger percentage of the gross national product is spent on defense of their coasts from rising seas than is spent on military defense in the United States.
(A) In Holland, a larger percentage of the gross national product is spent on defense of their coasts from rising seas than is spent on military defense in the United States.
(B) In Holland they spend a larger percentage of their gross national product on defending their coasts from rising seas than the United States does on military defense.
(C) A larger percentage of Holland’s gross national product is spent on defending their coasts from rising seas than the United States spends on military defense.
(D) Holland spends a larger percentage of its gross national product defending its coasts from rising seas than the military defense spending of the United States.
(E) Holland spends a larger percentage of its gross national product on defending its coasts from rising seas than the United States does on military defense.
I think this one follows nicely from the conversation that we had last week. We’ve got another comparison structure, we’ve got an entire sentence underlined, and yet there are also some differences here.
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Comparisons in GMATPrep Sentence Correction
I’ve got a fascinating (and infuriating!) GMATPrep problem for you today; this comes from the free problem set included in the new GMATPrep 2.0 version of the software. Try it out (1 minute 15 seconds) and then we’ll talk about it!
* Unlike computer skills or other technical skills, there is a disinclination on the part of many people to recognize the degree to which their analytical skills are weak.
(A) Unlike computer skills or other technical skills, there is a disinclination on the part of many people to recognize the degree to which their analytical skills are weak.
(B) Unlike computer skills or other technical skills, which they admit they lack, many people are disinclined to recognize that their analytical skills are weak.
(C) Unlike computer skills or other technical skills, analytical skills bring out a disinclination in many people to recognize that they are weak to a degree.
(D) Many people, willing to admit that they lack computer skills or other technical skills, are disinclined to recognize that their analytical skills are weak.
(E) Many people have a disinclination to recognize the weakness of their analytical skills while willing to admit their lack of computer skills or other technical skills.
I chose this problem because I thought the official explanation fell short; specifically, there are multiple declarations that something is wordy or awkward. While I agree with those characterizations, they aren’t particularly useful as teaching tools “ how can we tell that something is wordy or awkward? There isn’t an absolute way to rule; it’s a judgment call.
Now, I can understand why whoever wrote this explanation struggled to do so; this is an extremely difficult problem to explain. And that’s exactly why I wanted to have a crack at it “ I like a challenge. : )
Okay, let’s talk about the problem. My first reaction to the original sentence was: nope, that’s definitely wrong. When you think that, your next thought should be, Why? Which part, specifically? This allows you to know that you have a valid reason for eliminating an answer and it also allows you to figure out what you should examine in other answers.
Before you read my next paragraph, answer that question for yourself. What, specifically, doesn’t sound good or doesn’t work in the original sentence?
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Modifier Madness: Breaking Down a GMATPrep Sentence Correction Problem
This week, we’re going to analyze a particularly tough GMATPrepSentence Correction question.
First, set your timer for 1 minute and 15 seconds and try the problem!
Research has shown that when speaking, individuals who have been blind from birth and have thus never seen anyone gesture nonetheless make hand motions just as frequently and in the same way as sighted people do, and that they will gesture even when conversing with another blind person.
A) have thus never seen anyone gesture nonetheless make hand motions just as frequently and in the same way as sighted people do, and that
B) have thus never seen anyone gesture but nonetheless make hand motions just as frequently and in the same way that sighted people do, and
C) have thus never seen anyone gesture, that they nonetheless make hand motions just as frequently and in the same way as sighted people do, and
D) thus they have never seen anyone gesture, but nonetheless they make hand motions just as frequently and in the same way that sighted people do, and that
E) thus they have never seen anyone gesture nonetheless make hand motions just as frequently and in the same way that sighted people do, and
Okay, have you got your answer? Now, let’s dive into this thing! What did you think when you read the original sentence?
This is a very tough problem; when I read the sentence the first time, I actually had to stop and try to strip the sentence down to its basic core, then figure out how the modifiers fit. Until I did that, I couldn’t go any further.
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Comparing Things in GMATPrep Sentence Correction
I’ve got a fascinating little GMATPrep problem for you today. Try it out (1 minute 15 seconds) and then we’ll talk about it!
* As the honeybee’s stinger is heavily barbed, staying where it is inserted, this results in the act of stinging causing the bee to sustain a fatal injury.
(A) As the honeybee’s stinger is heavily barbed, staying where it is inserted, this results in the act of stinging causing
(B) As the heavily barbed stinger of the honeybee stays where it is inserted, with the result that the act of stinging causes
(C) The honeybee’s stinger, heavily barbed and staying where it is inserted, results in the fact that the act of stinging causes
(D) The heavily barbed stinger of the honeybee stays where it is inserted, and results in the act of stinging causing
(E) The honeybee’s stinger is heavily barbed and stays where it is inserted, with the result that the act of stinging causes
I chose this problem because it addresses multiple tricky issues that are perhaps easy to hear “ if you have built a good GMAT ear “ but are difficult to explain or articulate. Anything that’s difficult to explain or articulate to yourself is harder to remember. It’s also easier for us to be fooled by our ears on such sentences.
Okay, let’s talk about the problem. My first reaction to the original sentence was: nope, that’s definitely wrong. Now, when the clock is actually ticking and I’m that confident, I don’t bother to try to explain to myself why, exactly, this one is wrong. I just cross off A and look for others that I can cross off for the same reasons I crossed off A.
Here, though, I hit a snag. When I went to the cross off anything else with the same mistake step there wasn’t a single word or location in the sentence on which I could concentrate.
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How To Minimize Careless Errors When Taking The GMAT
Remember those times when you were sure you got the answer right, only to find out that you got it wrong? For a moment, you even think that there must be a mistake in the answer key. Then, you take a look at the problem again, you check your work, and you say, I can’t believe I did that! You knew exactly how to do this problem and you should have gotten it right, but you made a careless mistake.
What’s a Careless Error?
By definition, a careless mistake occurs when we did actually know all of the necessary info and we did actually possess all of the necessary skills, but we made a mistake anyway. We all make careless mistakes (yes, even the experts!); over 3.5 hours, it’s not reasonable to assume that we can completely avoid making careless mistakes. Our goal is to learn how to minimize careless mistakes as much as possible.
How Can We Minimize Careless Errors?
Isn’t the whole point of a careless error that we don’t know when we’re going to make them? They just happen randomly and we can’t control that!
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Tackling Find the Assumption Critical Reasoning Problems
Find the Assumption questions are very common Critical Reasoning question types. If you don’t yet know the general process for tackling Critical Reasoning problems, learn how before you keep reading this article.
Ready to try a question? Set your timer for 2 minutes and try this GMATPrep problem:
In a study conducted in Canada, servers in various restaurants wrote Thank you on randomly selected bills before presenting the bills to their customers. Tips on these bills were an average of three percentage points higher than tips on bills without the message. Therefore, if servers in Canada regularly wrote Thank you on restaurant bills, their average income from tips would be significantly higher than it otherwise would have been.
Which of the following is an assumption on which the argument relies?
(A) The Thank you messages would have the same impact on regular patrons of a restaurant as they would on occasional patrons of the same restaurant.
(B) Regularly seeing Thank you written on their bills would not lead restaurant patrons to revert to their earlier tipping habits.
(C) The written Thank you reminds restaurant patrons that tips constitute a significant part of the income of many food servers.
(D) The rate at which people tip food servers in Canada does not vary with how expensive a restaurant is.
(E) Virtually all patrons of the Canadian restaurants in the study who were given a bill with Thank you written on it left a larger tip than they otherwise would have.
Got your answer? Let’s start going through this one!
Step 1: Identify the Question
The question stem contains the word assumption, which is a pretty good clue that this is a Find the Assumption (FA) question. This question type always contains a conclusion and I know it’s important to find that conclusion. Also, if I can, I’m going to brainstorm any assumptions I can think of without taking too much time.
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