Today we’re going to talk about statistics problems in which we have to combine knowledge of more than oneconcept.Try this GMATPrep problem first; set your timer for 2 minutes and go!

Last month 15 homes were sold in Town X. The average (arithmetic mean) sale price of the homes was $150,000 and the median sale price was $130,000. Which of the following statements must be true?

I. At least one of the homes was sold for more than $165,000.

II. At least one of the homes was sold for more than 130,000 and less than 150,000.

III. At least one of the homes was sold for less than $130,000.

(A) I only

(B) II only

(C) III only

(D) I and II

(E) I and III

Sigh. I hate roman numeral questions. I have to do more work to solve the problem, and I never like that. : )

Read more

Modifiers have always been commonly tested on the GMAT and emphasis on meaning has increased recently. In addition, these two areas can often be quite tricky “ it’s hard to articulate exactly what the issues are sometimes. So let’s try talking one through. This problem is from GMATPrep. Set your timer for 1 minute 15 seconds and go for it!

*  “Initiated five centuries after Europeans arrived in the New World on Columbus Day 1992, Project SETI pledged a $100 million investment in the search for extraterrestrial intelligence.

(A) Initiated five centuries after Europeans arrived in the New World on Columbus Day 1992, Project SETI pledged a $100 million investment in the search for extraterrestrial intelligence.

(B) Initiated on Columbus Day 1992, five centuries after Europeans arrived in the New World, a $100 million investment in the search for extraterrestrial intelligence was pledged by Project SETI.

(C) Initiated on Columbus Day 1992, five centuries after Europeans arrived in the New World, Project SETI pledged a $100 million investment in the search for extraterrestrial intelligence.

(D) Pledging a $100 million investment in the search for extraterrestrial intelligence, the initiation of Project SETI five centuries after Europeans arrived in the New World on Columbus Day 1992.

(E) Pledging a $100 million investment in the search for extraterrestrial intelligence five centuries after Europeans arrived in the New World, on Columbus Day 1992, the initiation of Project SETI took place.

As we discuss this problem, I really want you to think about how to articulate why something is incorrect (or correct). Pretend you’re the teacher and you have to explain it to your students. Also, I’m going to give us a bit of a handicap. You aren’t allowed to use this reason: It changes the original meaning of the sentence.

Read more

Everyone struggles with some amount of anxiety when taking a test like the GMAT, but some people struggle more than others. Stress can also affect your preparation before you ever get to the test center “ if you’re too stressed out when studying, that will hurt your ability to make and recall memories. So what can we do to reduce studying and test-taking stress?

Know what’s coming

The more you’re prepared for what you’re going to face, the less stressed you’ll be. This won’t completely eliminate your anxiety “ nothing will “ but it can help to reduce stress to more manageable levels.

One major source of stress on this test is the feeling that you need to get everything right (and getting stressed out when you hit questions that you know you’re getting wrong). Read this article: In It To Win It. The nutshell: you’re not trying to get everything right. Nobody gets everything right, including me and other 99th percentile testers!

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.

A student recently asked me to show an example of how I read and take notes on a reading comprehension passage. In this older article, I discussed how to read through a RC passages in general, but I didn’t show an example. If you haven’t already read the older article, read that first; then come back here to see an example. 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.

Have you been studying for a while now but having trouble getting to your goal score or making the kind of improvement that you want to make? If you’re getting frustrated with your progress (or lack thereof), let’s try to figure out what’s going on. It’s entirely possible that you have some problems of which you’re unaware, or that you’re studying in an inefficient or ineffective way.

There are a number of additional articles linked in this article. If you read something that applies to your situation, click on all the links you see in that section. Also, ask for advice! There are so many resources out there that it can be overwhelming, but most companies offer free advice and you can also benefit from talking to fellow students. Read more

Don’t worry. We’ll address what to do if you’re already studying—and struggling in some ways—in another article coming later this week.

If you’re just starting out and trying to figure out what to do, we’ve got several big categories of things to discuss: mindset, devising a study plan, and learning how to study.

Read more

This is probably the shortest—and most important—article I’ve written in a year. It’s just a little story, but it’s the story of a crucial epiphany one of my students (and I) just had.

Last night, at the end of a class I was teaching, one of my students began asking questions about timing and guessing on the GMAT. He’s really struggling with the idea that he has to let some questions go and that he’s going to get a decent number of questions wrong. I told him he’s not alone; most students have significant difficulty accepting this idea—and those who can’t accept it almost never reach their goal scores.

As we discussed the boring details of how the GMAT works, he acknowledged that he knew he had to do what I said (because I’m the expert ?), but he was having a tough time because, normally, he’s in it to win it.

(For those who aren’t familiar with that expression, it means that, if you’re playing a game, you’re always going for it and trying to win.)

When he said that, a light bulb went off in my head, and I then said something to him that made a light bulb go off in his head. I said:

Yes, but are you playing the right game?

Read more

Patterns in Divisibility Problems

Today we’re going to tackle a couple of tough divisibility problems from GMATPrep. The two problems I’ve chosen share some interesting characteristics. Here’s your first one; set your timer for 2 minutes and go!

If n is a multiple of 5 and n = p ² q , where p and q are prime numbers, which of the following must be a multiple of 25?”
(A)  p ²

(B)  q ²

(C) p q

(D) p²q²

(E) p³q^“

Hmm. So p and q are primes. They could be 2, 3, 5, 7 or so on. It doesn’t say that p and q are different prime numbers, so they could also be the same number. And I’m going to use some theory here: if p²q equals n and n is a multiple of 5, then that 5 must be contained in either p or q. And since those two numbers are primes, either p or q is 5. (Or maybe both are!)

Read more

This week, we’re going to discuss Evaluate critical reasoning problems. Evaluate what? We’re trying to evaluate an assumption the author uses to draw a conclusion, so these Evaluate questions are a subset of the Assumption Family of questions.

Let’s say we’re given this argument:

In order to increase its profits, MillCo plans to reduce costs by laying off any non-essential employees.

Does that sound like a good plan? Profits equal revenues minus costs. What’s MillCo assuming in claiming that laying off non-essential employees will result in increased profits? For one thing, MillCo is assuming that revenues won’t drop as much as or more than the expected cost savings; if that occurred, MillCo’s profits wouldn’t increase.

An Evaluate question might say something like what would be most useful to know in order to evaluate MillCo’s plan? A correct answer might read:

Whether revenues will be affected adversely enough to threaten MillCo’s profit structure.

Let’s say that answer is no: MillCo’s revenues won’t be affected adversely enough. In that case, MillCo’s argument is strengthened. If, on the other hand, the answer is yes, MillCo’s revenues will be affected adversely enough, then MillCo’s argument is weakened. This answer, then, is designed to test the assumption; it helps to determine whether the assumption is valid. It does not tell us, however, that the assumption definitely is, or is not, valid.

Read more

Last week, we discussed the general process for tackling Critical Reasoning problems. This week, let’s go through a specific problem together using our process.

First, a reminder. Our 4-step process is:

• Step 1: Identify the question.
• Step 2: Deconstruct the argument.
• Step 3: State the Goal.
• Step 4: Work from wrong to right.

Okay, set your timer for 2 minutes and try this GMATPrep problem:

Read more