Know the GRE: How to solve Quant problems

For those of you hoping to do graduate studies abroad, it's likely that you'll have to take at least one exam. Business and management students must ace the GMAT, law students the LSAT and medical students the MCAT.

But what about the rest of you? The political researchers, the British literature experts, the mathematicians? What stands between you and acceptance at a top-flight graduate school abroad?

Meet the Graduate Record Examination (more commonly known as GRE.

Introduction

GRE is a computer based adaptive test available year-round at test centers throughout the world. It is an international exam that measures Quantitative reasoning, verbal reasoning, critical thinking and analytical writing abilities of test takers.

GRE (General Test) tests the fundamental skills of applicants and does not require any subject-specific theoretical study where as there is GRE subject test that is mandatory along with GRE General test for admission to certain specialised courses.

GRE exam has three distinct sub-divisions viz. Verbal Section, Quantitative Reasoning section and Analytical Writing Section. The table below explains them in detail:

 

GRE Quant Section:

The math section in GRE involves three types of questions viz. Problem Solving, Quantitative Comparisons and Graph based questions. The following chart explains the division of questions between the three sections:

From November 2007 Quantitative section in GRE will have new question type i.e. student response questions. No options will be given for this question. Questions of this type ask you to enter your answer either as a number in a single answer box or as a fraction in two separate boxes

GRE Math: Some Problem solving Strategies

The first and the most important consideration is the preparation form. GRE - Problem Solving is 'exhaustive practice'. One must have tried all the kinds of questions possible on problem solving before you get hold of the sample questions given by ETS in the CD that is sent to the registered test takers.

A lot of sources are available online and one such source is online-tests section at http://www.tcyonline.com/. One can take as much as 50 tests on GRE there. Another way is to join various online groups and communities to get the first hand information of the recent questions in GRE.

Following are the important tips that will help you attempt problem solving questions effectively and accurately:

• Always go through the options while reading and formulating the problem. Options always give some hint and save time.
• Try to express the information given in the problem into mathematical expressions.
• Elimination method is the best in most of the problems.
• Never involve in lengthy calculations.
• For questions involving variables, plug in some value for the variables as it is much easier to deal with numeric values rather than variables.

 Problem Solving sample questions:

1. If the ratio of the number of red cars to the number of white cars parked at a parking lot is 3 to 2. By what percentage is the number of red cars more than the number of white cars?

            (A) 25%           (B) 50%           (C) 75%           (D) 100%         (E) 150%

2. If p and q are distinct prime numbers, which of the following statements can never be true?

            (A) p/q is not an integer                                     (B) (p - 1) q is even     

            (C) L.C.M of p and q is pq                                 (D) H.C.F. of p and q is 1

            (E) pq is prime

3. Consider the function P (a) = 0.036 x 10^a/0.06 x 10^2a-5 , If P (a) = 6 x 10^-5; 'a' is equal to

             (A) -8         (B) -5              (C) 0                (D) 5               (E) 8

4. A line L is parallel to the line M that passes through point P (1, b) and intersects y- axis at (0, 2). If the slope of the line L is 3b + 5, what is the slope of line M?

            (A)  -11/2    (B) -2/7           (C)  -7/2          (D) 2/11             (E) 11/2


5. l, m, n are non-zero integers such that l = -2m and |n| = min {|l|, |m|} + max {|l|, |m|}. If l = - 4, what could be the value of 'n'?

            (A) -4              (B) -2             (C) 0                (D) 2                (E) 6

6. A three-digit number 'xyz' is such that yz is divisible by 15. For what value of x, xyz will be divisible by 15?

            (A) 1                (B) 2                (C) 3                (D) 4                (E) 5

7. A pattern is made using different blocks in the repeating pattern black, red, white, blue, and yellow. If the total number of blocks used is 'X' and the pattern starts and ends with a black block, what will be left when X is divided by 5?

            (A) 0                (B) 1                (C) 2                (D) 3                (E) 4

8. A box contains 6 blue marbles and 5 white marbles. Andy draws a blue marble from the bag and replaces it with a black marble. James now draws a marble from the box. What is the probability that the he will draw a blue marble?

(A) 6/11             (B) 5/11             (C) 6/10             (D) 5/10              (E) 5/12

9. If P is an integer such that P= 13.11.9.7.5.3.2/55q, which of the following can never be the value of q?

(A) 26              (B) 39               (C) 42               (D) 45              (E) 63

10. If - 3 < = x < = 7 and - 6 < = y < = 2, what is the smallest possible value of 3x - y?

*There are no given options here. You must choose without the aid of options. This is a new question type on GRE this year.

 

 

• Answers and detailed strategic explanations

Nitin is a senior Quantitative Reasoning Trainer with Top Careers & You. He can be contacted at tcychd@tcyonline.com. You may visit www.tcyonline.com/gre.php to get 50+ free tests on GRE.