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# Category: GMAT Data Sufficiency

• ## GMAT Data Sufficiency Logic: Tautological Statements

First, here are four DS practice problems:   2) In the diagram above, the circle has its center at point O. Line BC touches the circle at point C, and the distance from B to C is 35 cm.  What is the area of the circle? Statement #1: AB = 25 cm Statement #2: angle OCB […]

• ## Tricky Data Sufficiency Questions: Explanations #7 and #8

Today, we’re going to review the last two questions from the Tricky Data Sufficiency Questions practice post. If you’re just tuning in, give the questions a shot, check your answers here, and then review the explanations to questions #1-2, #3-4, and #5-6. Ready? Let’s move along. Question #7 7. If p + q = 2r […]

• ## Tricky Data Sufficiency Questions: Explanations #5 and #6

Today, we present the explanations for questions #5-6 from our Tricky Data Sufficiency Questions challenge. Be sure to check out the explanations for questions #1-2, and questions #3-4 before moving on to today’s post. Let’s get started.   Question #5 5. What is the value of m+n? (1) mn = -8 (2) -2m = n […]

• ## Tricky Data Sufficiency Questions: Explanations #3 and #4

Today, we present the explanations to questions #3-4 from our Tricky Data Sufficiency Questions challenge post. You can find the explanations to questions #1-2 here. Let’s get started.   Question #3 3. If 2x = 2y – 3z, what is the value of z? (1) y = x + 2 (2) x = y – […]

• ## Tricky Data Sufficiency Questions: Explanations #1 and #2

Today, we present the explanations for the first two questions in our Tricky Data Sufficiency Questions post. Let’s get started. Question #1 1. What is the value of x? (1) 5 x + 3 y = 15   (2) y = 5 – (5/3) x (A) Statement (1) ALONE is sufficient, but statement (2) alone […]

• ## Tricky Data Sufficiency Questions: Answer Key

On Monday, we presented a series of tricky data sufficiency questions, to test whether or not you’re able to steer clear of all the traps. Today, we present the answers to those questions, so that you can check your work. Over the next week or so, we will publish posts with in-depth explanations of how […]

• ## GMAT Data Sufficiency: Rephrasing the Question

First, here are 12 practice problems.  Solutions will be given at the end of this article. 1) Two teachers, Ms. Ames and Mr. Betancourt, each had N cookies.  Ms. Ames was able to give the same number of cookies to each one of her 24 students, with none left over.  Mr. Betancourt also able to […]

• ## Tricky Data Sufficiency Questions

My most recent blog posts have concerned tricky Data Sufficiency questions about systems of equations. Specifically, they’ve been about what can go wrong when you misremember a rule and assume that it’s possible to solve for two variables if and only if you’re given two equations, and generally that it’s possible to solve for n […]

• ## GMAT Data Sufficiency: More Practice Questions

In the following problems, remember: no calculator!  Difficulty levels range from medium to hard. 2) Maggie is 15 years older than Bobby.  How old is Bobby? Statement #1: In 3 years, Maggie’s age will be 50% larger than Bobby’s age. Statement #2: Years ago, when Maggie was 25 years old, Bobby was 10 years old. […]

• ## GMAT Tricks with Systems of Equations: Part 5

A lot of GMAT test-takers vaguely remember a rule from high school, that it’s possible to solve for two variables if and only if you’re given two equations, and generally that it’s possible to solve for n variables if and only if you’re given n equations. Unfortunately, that rule isn’t quite correct as written, and […]