Last time, we talked about how to find a starting point on a Sentence Correction problem when the starting point doesn’t leap out at you. If you haven’t read that article yet, go ahead and do so.

The first step of the SC process is a First Glance, something that didn’t help out a whole lot on last week’s problem. Let’s try out the First Glance again and see what happens!

This GMATPrep® problem is from the free exams.

* “Often incorrectly referred to as a tidal wave, a tsunami, a seismic sea wave that can reach up to 150 miles per hour in speed and 200 feet high, is caused by underwater earthquakes or volcanic eruptions.

“(A) up to 150 miles per hour in speed and 200 feet high, is

“(B) up to 150 miles per hour in speed and heights of up to 200 feet, is

“(C) speeds of up to 150 miles per hour and 200 feet high, are

“(D) speeds of up to 150 miles per hour and heights of up to 200 feet, is

“(E) speeds of up to 150 miles per hour and as high as 200 feet, are”

What did you do for the First Glance? The glance is designed to give you an upfront hint about one issue that the sentence might be testing before you actually start reading the full sentence. Take a look at the beginning of the underline, including the beginning of all five answer choices.

The split is between up to and speeds of up to. There isn’t an obvious grammar rule here, so the issue is likely to revolve around meaning: do we need to say speeds of or is it enough to say just up to?

Think about this while reading the original sentence. What do you think?

The phrase reach up to could go in several different directions—is it going to say up to 150 miles in length? up to 150 feet high?—so it’s preferable to clarify right up front that the wave is reaching speeds of up to 150 miles per hour.

In addition, the sentence contains parallelism:

can reach up to X [150 miles per hour in speed] and Y [200 feet high]

The portion before the parallelism starts must apply to both the X and Y portions, so the original sentence says:

can reach up to 200 feet high

That might sound kind of clunky and it is: up to and high are redundant.

Okay, answer (A) is incorrect and answer (B) repeats both issues (it neglects to specify speeds of up to 150 and it contains faulty parallelism.).

Check the parallelism in the other choices:

“(C) speeds of up to [150 miles per hour] and [200 feet high]

“(D) [speeds of up to 150 miles per hour] and [heights of up to 200 feet]

“(E) speeds of [up to 150 miles per hour] and [as high as 200 feet]”

In answer (C), the Y portion is the measurement (200 feet), so the X portion should also be the measurement…but it’s nonsensical to say speeds of up to 200 feet high. Likewise, in (E), the Y portion is a prepositional phrase, so it matches the prepositional phrase in the X portion. Now, the sentence says speeds of as high as 200 feet—equally nonsensical.

The only one that makes sense is answer (D): speeds of up to 150 and heights of up to 200.

The correct answer is (D).

You might also have noticed, in the original sentence, that the last underlined word is the verb is. Sentence Correction problems always have at least one difference at the beginning of the underline and at the end, so glance down the end of the choices.

Interesting! Is vs. are. What subject goes with this verb? Here’s the original sentence again:

“Often incorrectly referred to as a tidal wave, a tsunami, a seismic sea wave that can reach up to 150 miles per hour in speed and 200 feet high, is caused by underwater earthquakes or volcanic eruptions.”

The modifiers have been crossed out. The subject is tsunami, a singular noun, so the verb should be the singular is. Answers (C) and (E) are incorrect for this reason.

Key Takeaways: The First Glance in Sentence Correction

(1) Before reading the original sentence, make it a habit to glance at the word or couple of words at the start of the underline and each answer choice. Sometimes, the split will be obvious: an is vs. are split, for example, clearly indicates subject-verb agreement.

(2) Sometimes the split will be less obvious, as with up to vs. speeds of up to. In this case, if the split is fairly easy to remember, just keep the variations in mind as you read the original sentence, so that you can analyze the difference right away. You may see immediately that speeds of up to is more clear, and your knowledge that the sentence is testing this meaning might also alert you to some of the meaning issues introduced by the faulty parallelism.

(3) Making a subject-verb match in the midst of a bunch of modifiers can be tricky. Learn how to strip the modifiers out and take the sentence down to its basic core structure.

* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

Want to learn more? Read on to part 3.

Manhattan GMAT

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Have you ever worked with someone who inevitably managed to come up with things to do that were a complete waste of time? Maybe it was an insecure boss who was never confident about what he was doing, so he went for the “everything and the kitchen sink” approach to generating deliverables in the last few days before the deadline. Or maybe it was a fellow student on a group project, someone so diligent (cough, cough) that she wanted to turn in a 20-page report when the teacher suggested 10 pages (and actually specified a 12-page limit).

You know who I’m talking about, right? We’ve all run across these situations in our academic or working lives. You want to be polite…but you also want to get your work done and not waste time on activities that don’t really help you reach the overall goal.

The GMAT is trying to waste your time

Okay, the test writers are not literally sitting there cackling and saying, “How can we get them to waste their lives?!?” But the overall sentiment still holds because of the way that the GMAT is constructed. You already know the classic “If you get something right, they give you something harder” pattern, right?

Well, at some point, that “something harder” is going to be something that isn’t worth your time. You’re probably not going to get it right no matter what you do. Even if you do, you’re going to use up valuable time that you could be using on other problems.

Most important of all, you’re going to be using up your finite brain energy on something that probably isn’t going to pay off. How many times in your life have you crashed towards the end of a test or a long day at work because your brain just couldn’t keep going any longer? The GMAT is a “where you end is what you get” test: if you crash before the end of the section, your score will suffer greatly.

This is basically no different than that co-worker who’s trying to get you to build a marketing presentation when the client has specifically requested that you analyze the pros and cons of acquiring a competitor. Tomorrow at the client meeting, it won’t matter how good your intentions were. Your client is going to be mad that you wasted time on something that doesn’t actually help them.

Read more

GMAC just released new 2015 editions of its three The Official Guide for GMAT® Review books. Here’s what you need to know as you decide whether to buy these books and how to use them.

What changed?

The three books in question are The Official Guide for GMAT Review 2015 (formerly known as the 13^th edition of the Official Guide, or OG), The Official Guide for GMAT Quantitative Review 2015 (formerly known as the 2^nd edition of the Quant Review), and The Official Guide for GMAT Verbal Review 2015 (formerly known as the 2^nd edition of the Verbal Review). I’ll refer to these throughout this article as OG2015, QR2015, and VR2015, respectively.

The questions (and explanations) contained in all three 2015 versions are the same as the questions (and explanations) in the previous versions. There are no new questions.

The new editions do come with special codes to access an online software program that contains the problems from the books. Now, when you want to do a set of random OG problems, you don’t have to create the sets for yourself—you can have the online software do it for you. (OG2015 also still provides online access to the 50 Integrated Reasoning questions that come with the 13^th edition of the book.)

The online software also has some short videos (one for each book) starring the incomparable Dr. Lawrence Rudner, Chief Psychometrician for GMAC, answering frequently asked questions from students.

How does the software work?

The software for all three books gives you the ability to choose Practice mode or Exam mode. In addition, OG2015 offers a Diagnostic test mode that contains the questions from chapter 3 of the printed book.

Certain features are offered in all three modes:

– Question Type, Number, and Difficulty. You can choose from among the different question types (PS, DS, SC, CR, RC), as well as by difficulty bucket (easy, medium, hard, or all). You can also decide how many questions you want to be in the set.

– Timing. The software will keep track of how much time you spend per question, as well as your overall time for that set of questions. (It does not, though, give you a time limit, so you will have to set one for yourself.)

– Bookmarks. You can bookmark problems that you want to remember for some reason—maybe your guesses or the ones that you want to try again before checking the answer or explanation.

– Calculator. Yes, the software offers a calculator, even though you’re not allowed to use a calculator on the quant section of the real test. My recommendation: pretend this button doesn’t exist.

– Pause. You can pause the question set. This is useful if someone suddenly rings your doorbell, but do not pause the software while continuing to work on the problem. Otherwise, your data will be skewed and you won’t really be able to tell what your strengths and weaknesses are.

In the Diagnostic and Exam modes, you can only move forward in the question set (as on the real exam), but in Practice mode, you can move back and forth. If you come back to a problem for the second time, the software will actually remember how much time you spent before and will start counting your time where you left off! I was really impressed with this feature.

I do have to warn you about three other somewhat-faulty features (maybe these will be changed in future). First, when you click to go to the next question, the software does not ask you to confirm. That’s fine in Practice mode, where you’re allowed to go backwards, but in Diagnostic and Exam modes, if you accidentally click “next question,” you will be moved to the next problem even if you have not yet entered an answer—and there is no way to go back.

Second, in any of the three modes, you’ll be able to go to a results screen when done with a question set. For both Exam and Practice modes, these question sets will be saved and you’ll be able to review them at any time in the future. In Diagnostic mode, however, you can only see the results screen right after you have finished the problem set. Once you close out of that area (or out of the software entirely), that data will disappear, so make sure you take screen shots of the results screen before you leave that area of the program. (In fact, I recommend taking the screen shots immediately after finishing a Diagnostic set. I accidentally clicked something that took me out of that part of the program and lost all of my data before I could review it.)

Third, in both Practice and Exam modes, the RC questions are offered one at a time, not in sets of 3 or 4 (as on the real test). For this reason, I recommend doing RC questions out of the physical book. Reading an entire passage only to answer a single question is not a good use of study time.

I was also excited to see that the Practice mode offered a “notes” feature, where you can actually type notes to yourself while working on the problem. I was disappointed that those notes seemed to disappear afterwards. When I was reviewing the results screen and the problem explanations, I couldn’t find any way to access my notes again.

How do I get the most out of these new books?

If you already have the previous incarnations of these books (OG13, VR2, and QR2), then I don’t actually recommend buying the new editions unless money is not a concern for you. The most important thing is to have access to the questions themselves. While the new software does make it much easier to set up problem sets, many people probably aren’t going to pay $46 just for that.

If you don’t yet have these books, though, then of course you’ll want to get the 2015 editions. In that case, here’s how I would use the new features:

1. In the first week or two of your study, take the Diagnostic mode tests. I would do these in 5 separate sittings, one for each question type. You don’t need to set yourself a hard overall time limit, but do pay attention to that clock and be honest with yourself when a problem just isn’t happening. Guess and move on. (Note: if you’re taking our class, then you can dispense with this step and save the problems for review later in your studies.)

2. As you work through whatever material you’re using to learn all about the math, grammar, and question types tested on the GMAT, you will initially try just a couple of OG problems that directly test whatever you recently studied. In this case, you won’t be using the OG software because the software doesn’t let you select by topic.

After you get at least halfway through your study material though (e.g., about 3 of our 5 quant books, or halfway through the chapters in the SC book), you can start to set up random sets of questions for yourself using the software’s Practice mode. When you’re offered a question on a topic you haven’t studied yet, just do your best; this will help you to have an idea of your strengths and weaknesses so that you know how much time to spend when you do get to that topic.

Whether you want to do random sets of problems or choose specific topics, here are some guidelines for creating your own OG problem sets.

3. Save Exam mode for a bit later in your studies, after you’ve been through all of your main study material once. Both Practice and Exam modes are pulling from the same pool of questions, but Exam mode imposes some additional restrictions that make your practice closer to the real test (for example, you can’t go back to questions that you’ve already completed).

In sum

Everyone should be studying with the Official Guide materials—nothing is better than the real thing! If you already have the 13^th edition or 2^nd edition books, don’t feel that you must buy the 2015 editions, but if you don’t, then certainly get the latest versions and take advantage of the new online problem set program.

Happy studying!

Did you know that you can attend the first session of any of our online or in-person GMAT courses absolutely free? We’re not kidding! Check out our upcoming courses here.

You’ve been thinking for a while now about going back to business school. You’ll go sometime in the future…but you haven’t started to do much about it yet.

Well, break out your pencils* and get ready to take advantage of your new membership in the GMAT Exercise Club! We’re going to set up a custom program for you to get the score you need by summer’s end—and then you can decide whether to apply this fall or to wait a year or two. Read more

Did you know that you can attend the first session of any of our online or in-person GMAT courses absolutely free? We’re not kidding! Check out our upcoming courses here.

Note: This is the old version of a series that has since been updated. You can find Stacey’s updated series here.

Last time, we talked about how to decide whether to study on your own, take a class, or work with a tutor. If you choose either of the latter two options, then you’ll want to make sure that you’re picking the best program and instructor for you—GMAT prep is too expensive to suffer through a bad program. Read more

Did you know that you can attend the first session of any of our online or in-person GMAT courses absolutely free? We’re not kidding! Check out our upcoming courses here.

Note: This is the old version of a post that has since been updated. Read Stacey’s new version here!

Summer is here again, along with the GMAT busy season. Application deadlines are just a few short months away! It’s time to get your GMAT study into gear. Read more

Memorize what? I’m not going to tell you yet. Try this problem from the GMATPrep® free practice tests first and see whether you can spot the most efficient solution.

All right, have you got an answer? How satisfied are you with your solution? If you did get an answer but you don’t feel as though you found an elegant solution, take some time to review the problem yourself before you keep reading.

Step 1: Glance Read Jot

Take a quick glance; what have you got? PS. A given equation, xy = 1. A seriously ugly-looking equation. Some fairly “nice” numbers in the answers. Hmm, maybe you should work backwards from the answers?

Jot the given info on the scrap paper.

Step 2: Reflect Organize

Oh, wait. Working backwards isn’t going to work—the answers don’t stand for just a simple variable.

Okay, what’s plan B? Does anything else jump out from the question stem?

Hey, those ugly exponents…there is one way in which they’re kind of nice. They’re both one of the three common special products. In general, when you see a special product, try rewriting the problem usually the other form of the special product.

Step 3: Work

Here’s the original expression again:

Let’s see.

Interesting. I like that for two reasons. First of all, a couple of those terms incorporate xy and the question stem told me that xy = 1, so maybe I’m heading in the right direction. Here’s what I’ve got now:

And that takes me to the second reason I like this: the two sets of exponents look awfully similar now, and they gave me a fraction to start. In general, we’re supposed to try to simplify fractions, and we do that by dividing stuff out.

How else can I write this to try to divide the similar stuff out? Wait, I’ve got it:

The numerator: 

The denominator: 

They’re almost identical! Both of the terms cancel out, as do the terms, leaving me with:

I like that a lot better than the crazy thing they started me with. Okay, how do I deal with this last step?

First, be really careful. Fractions + negative exponents = messy. In order to get rid of the negative exponent, take the reciprocal of the base:

Next, dividing by 1/2 is the same as multiplying by 2:

That multiplies to 16, so the correct answer is (D).

Key Takeaways: Special Products

(1) Your math skills have to be solid. If you don’t know how to manipulate exponents or how to simplify fractions, you’re going to get this problem wrong. If you struggle to remember any of the rules, start building and drilling flash cards. If you know the rules but make careless mistakes as you work, start writing down every step and pausing to think about where you’re going before you go there. Don’t just run through everything without thinking!

(2) You need to memorize the special products and you also need to know when and how to use them. The test writers LOVE to use special products to create a seemingly impossible question with a very elegant solution. Whenever you spot any form of a special product, write the problem down using both the original form and the other form. If you’re not sure which one will lead to the answer, try the other form first, the one they didn’t give you; this is more likely to lead to the correct answer (though not always).

(3) You may not see your way to the end after just the first step. That’s okay. Look for clues that indicate that you may be on the right track, such as xy being part of the other form. If you take a few steps and come up with something totally crazy or ridiculously hard, go back to the beginning and try the other path. Often, though, you’ll find the problem simplifying itself as you get several steps in.

* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

Welcome to the final installment in a series of three articles about meaning and sentence structure in sentence correction. Our first one tested meaning and also covered issues related to having to break the sentence into chunks. In the second, we talked about how to use that chunk idea to strip the sentence down to the core structure vs. the modifiers.

Today, I’ve got a third GMATPrep® problem for you following some of these same themes (I’m not going to tell you which ones till after you’ve tried the problem!).

* “Today’s technology allows manufacturers to make small cars more fuel-efficient now than at any time in their production history.

“(A) small cars more fuel-efficient now than at any time in their

“(B) small cars that are more fuel-efficient than they were at any time in their

“(C) small cars that are more fuel-efficient than those at any other time in

“(D) more fuel-efficient small cars than those at any other time in their

“(E) more fuel-efficient small cars now than at any time in”

The first glance doesn’t indicate a lot this time. The answers change from small cars to more (fuel-efficient small cars), which isn’t much of a clue. Go ahead and read the original sentence.

What did you think? When I first read it, I shrugged and thought, “That sounds okay.” If you can’t come up with something to tackle from the first glance or the first read-through, then compare answers (A) and (B), looking for differences.

Hmm. I see—do we need to say that are more fuel-efficient? Maybe. Answer (C) uses that same structure. Oh, hey, answer (C) tosses in the word other! I know what they’re doing!

If you’ve seen the word other tested within a comparison before, you may know, too. If not, get ready to make a note. Take a look at these two sentences:

Read more

Last time, we tried a problem that tested meaning; we also discussed how to compare entire chunks of the answer choices. Today, we’re going to combine those two things into a new skill.

Try this GMATPrep® problem from the free exams and then we’ll talk about it.

* “The striking differences between the semantic organization of Native American languages and that of European languages, in both grammar and vocabulary, have led scholars to think about the degree to which differences in language may be correlated with nonlinguistic differences.

“(A) that of European languages, in both grammar and vocabulary, have

“(B) that of European languages, including grammar and vocabulary, has

“(C) those of European languages, which include grammar and vocabulary, have

“(D) those of European languages, in grammar as well as vocabulary, has

“(E) those of European languages, both in grammar and vocabulary, has”

At first glance, the underline isn’t super long on this one, Glance down the first word of each answer. What does a split between that and those signify?

Both are pronouns, so they’re referring to something else in the sentence. In addition, one is singular and one is plural, so it will be important to find the antecedent (the word to which the pronoun refers).

Next, read the original sentence. What do you think? It isn’t super long but it still manages to pack in some complexity. Learn how to strip it down and you’ll be prepared for even more complex sentence structures.

My first thought was: okay, now I see why they offered that vs. those. Should the pronoun refer to the plural differences or to the singular organization?

It could be easy to get turned around here, so strip down the sentence structure:

Read more

Did you know that you can attend the first session of any of our online or in-person GMAT courses absolutely free? We’re not kidding! Check out our upcoming courses here.

I first wrote about this topic back in 2010. I’ve seen so many people lately on the forums who are going for a 750 or 760 score or higher that I decided to revive the conversation. Read more