# Picking Numbers on GMAT Data Sufficiency: Permissible vs. Sufficient

One of the hallmark points of confusion on GMAT Data Sufficiency is the dreaded Yes/No question.

In a Value question, such as “What is the value of x?” the question of sufficiency is a familiar one: if you can solve for x, you have sufficiency. But in a Yes/No question, especially when variables are involved, finding a solid answer can be a much cloudier process.

Sample GMAT Data Sufficiency Yes/No Question

The best way to clear this fog is with a concrete example. Let’s look at this Data Sufficiency question, along with its first statement:

Is x positive?

(1) x^2 > 1

Is Statement (1) sufficient to answer the question? Unless you have a comprehensive understanding of the underlying Number Properties at work here, your first reaction to this statement is likely to try out different numerical values for x, because working with real numbers instead of variables will … **Read full post**

# The 4 Sections of the GMAT Practice Test

What is the GMAT (Graduate Management Admissions Test)?

If you’re thinking of going to business school but haven’t yet looked into GMAT test dates or taken a GMAT practice test, not to fear! You’ve come to the right place to learn about the format, timing, and scoring of the GMAT test and GMAT practice test, the latter of which we offer free on our website year-round.

The CAT (computer adaptive test) and GMAT scoring

Understanding how the CAT works and approaching GMAT practice questions with a few targeted strategies will help you get in fighting form for your GMAT test date.

A CAT is more than just a digital version of a written exam. It actually adapts to your performance as you’re taking the test. When you begin each category, the computer assumes you have an average score and gives you a question of medium difficulty. As you answer … **Read full post**

# Get Your Fresh GMAT Practice Question Here!

Yesterday, we posted a GMAT practice question on Facebook. It got a lot of attention and many responses. Here it is again:

What is the value of b if a = ?

Our Facebook audience mostly answered A, with a few votes for D. The correct answer is indeed A, and here’s why…

First, you can multiply both sides of the equation in the question stem by to make it clear that . Then, look for values a, c and .

- Statement (1) is exactly what is needed – it gives you a precise value for . Statement (1) is sufficient, so eliminate answer choices C and E.
- Statement (2) alone, however, leads to two possible values for b, because you’d have to substitute the square roots of 25 for a, and those square roots are BOTH positive AND negative 5 (remember this! The GMAT likes to

# Free GMAT Sample Class

If you need help with your GMAT prep, we’ve got you covered. Now is your chance to see one of our GMAT experts in action, breaking down the GMAT exam and introducing you to proven Kaplan methods and strategies that will allow you to dominate your competition on GMAT Test Day.

If you attended any of the free GMAT practice tests that we held recently, then you’ve already met some of our GMAT experts. What better way to continue your GMAT prep than to attend a free, live, online session that’s focused on introducing you to the most efficient approach to every question type that you’ll see on the GMAT?

Here’s an example of the type of questions you’ll see in our upcoming GMAT Sample Class:

The youngest of 4 children has siblings who are 3, 5, and 8 years older than she is. If the average (arithmetic mean) age … **Read full post**

# Exponent Errors on the GMAT

Exponent questions are among those that give GMAT-preppers the most difficulty. The key to answering exponent questions correctly is to remember all of the rules you must follow. For example, knowing that ab x ac = ab+c, and ab x cb = (ac)b will be essential to answering exponent questions correctly.

However, you also want to avoid common exponent mistakes. This is especially important because wrong answer choices in exponent questions, as with the rest of the GMAT, will be based on common test-taker errors.

The most common mistake test-takers make on exponent questions is to erroneously believe that ab + ac = ab+c. Remember, exponent rules refer to multiplication and division, not addition and subtraction. When you encounter an exponent question on addition or subtraction, you will usually need to factor out like terms in order to simplify. For example, if a problem states that 2210 + 225, rewrite … **Read full post**

# Kaplan GMAT Sample Problem: Probability and “at least”

Probability questions can be among some of the more advanced and trickier problems you’ll face on the GMAT Quantitative section. Be sure to pay attention to the wording of word problems such as this one; in this case when asked about a scenario with “at least twice”, it will be more efficient to solve for that NOT happening and subtract from 1 (since the probability of something happening plus the probability of that same thing NOT happening should add up to 1, or 100%.)

Question:

A fair coin is tossed five times. What is the probability that it lands heads up at least twice?

(A) 1/16

(B) 5/16

(C) 2/5

(D) 13/16

(E) 27/32

Solution:

The key phrase to solving this sample GMAT problem is ‘at least twice.’ This means that out of our five flips, two, three, four and five heads are all desired outcomes. On problems such … **Read full post**

# Kaplan GMAT Sample Problem: Probability Problem Solving

Try this advanced GMAT probability question, testing your knowledge of the ins and outs of how probability works.

Problem:

The events A and B are independent. The probability that event A occurs is 0.6, and the probability that at least one of the events A and B occurs is 0.94. What is the probability that event B occurs?

(A) 0.34

(B) 0.65

(C) 0.72

(D) 0.76

(E) 0.85

Solution:

In order to find the probability that event B occurs in this problem, we need to set up and equation that includes the probabilities we are given and allows us to solve for B. We are told that the probability that at least one of A or B occurring is 0.94. ‘At least one of A or B’ means that an outcome is desired if A occurs and B does not, B occurs and A does not or A and … **Read full post**

# Kaplan GMAT Sample Problem: Average Rate

What should you do when you see a GMAT problem asking you for the average rate over an entire journey? Try your hand at this problem and let’s see.

Problem:

A canoeist paddled upstream at 10 meters per minute, turned around, and drifted downstream at 15 meters per minute. If the distance traveled in each direction was the same, and the time spent turning the canoe around was negligible, what was the canoeist’s average speed over the course of the journey, in meters per minute?

(A) 11.5

(B) 12

(C) 12.5

(D) 13

(E) 13.5

Solution:

In average rate problems many students forget that average rate means total distance divided by total time and not the average of the rates. This is especially true on problems, such as this one, that give the test-taker two rates, but no distances and no times. When this occurs, the most concrete strategy, … **Read full post**

# Kaplan GMAT Sample Problem: Prime Factors

Dealing with prime numbers and prime factors is an essential GMAT skill. Technically it is a skill we learned as early as elementary school/early school age, however just because it was learned in childhood does not mean that these questions are necessarily easy for GMAT test-takers. First of all, dealing with prime factors may not be something we do on a daily basis, so you’ll want to be sure you practice during your studies. Secondly, sometimes the wording or steps along the way can be challenging on the GMAT, not to mention the time limit. Here is a fairly straightforward question, though it may take some time to work through.

Problem:

What is the smallest positive integer that is a multiple of 18, 20, 24, 25 and 30?

(A) 360

(B) 900

(C) 1,800

(D) 2,400

(E) 3,600

Solution:

While taking each answer choice, starting with the smallest, and … **Read full post**

# Kaplan GMAT Sample Problem: Data Sufficiency Averages

GMAT Data Sufficiency questions can take simple concepts like averages and have test-takers pausing or falling into traps because of the way they are worded, and the fact that you have to keep in mind what your goal is with Data Sufficiency—to find out whether or not you have sufficient information to answer the question!

Problem:

Each of the 8 numbers s, t, u, v, w, x, y and z is positive. Is the average (arithmetic mean) of s, t, u, v, w, x, y and z greater than 46?

(1) The average (arithmetic mean) of s, t, u, v and w is greater than 74.

(2) The average of x, y and z is greater than 120.

Solution:

Before evaluating the statements, you should reword the question. We are asked if the average of a list of numbers is greater than 46. Since average is equal to the … **Read full post**

## @KaplanGMATPrep

## July 13

Road to #bschool events are around the corner. Check out the Carlson School of Management profile to get ready http://t.co/rvXWxZk5Vz #GMAT

## Kaplan GMAT Prep

## July 10

Anyone thinking about heading to the midwest for bschool? Check out this week's bschool profile, University of Minnesota Carlson School of Management: http://bit.ly/16rXsKY

University of Minnesota: Carlson School of Management

blog.kaplangmat.com

The University of Minnesota's Carlson School of Management, located in the twin cities of Minneapolis and St. Paul, has a rich history and over 50,000...