Problem-solving questions are standard multiple-choice questions with five answer choices: A, B, C, D, and E. These problems test your basic math skills, your ability to apply elementary math concepts, and your ability to reason quantitatively.

Problem-solving questions cover three subject areas: arithmetic, elementary algebra, and geometry. The number of questions for each of these three subjects is in the neighborhood of

• Arithmetic: 13
• Elementary algebra: 6
• Geometry: 3

When working on a problem-solving question, make sure that you read the question carefully, know exactly what you have to find, solve the problem, and select the best of the answer choices given.

Remember: All numbers in the quantitative section are real numbers, and all figures shown are drawn as accurately as possible, unless stated otherwise. Straight lines may sometimes appear jagged on the computer screen.

When working on the quantitative section of the GMAT, keep in mind the following:

• It is important to pace yourself. You have 75 minutes to do 37 questions, which is approximately 2 minutes per question.
• You may not skip over a question. The computer will not present the next question until you've answered the current one on the screen.
• Make an educated guess if you aren't sure about the answer. There is a penalty for wrong answers, but there is also a penalty for unanswered questions, so if you're struggling with a particular question, you're better off making an educated guess and moving on.
• Calculators are not allowed.

Sample practice question: Arithmetic

There are 200 marbles in a box. All the marbles are either red or blue. If there are 40 more red marbles than blue, how many red marbles are there in the box?

A. 40

B. 80

C. 120

D. 160

E. 180

The correct answer is C. Let x be the number of blue marbles, and x + 40 be the number of red marbles. There are 200 marbles in the box, so you have x + x + 40 = 200, which is equivalent to 2x + 40 = 200, or x = 80. Thus, the number of red marbles is x + 40 = 120.

Sample practice question: Algebra

Three times a number is the same as the number added to 60. What is the number?

A. 15

B. 20

C. 30

D. 45

E. 180

The correct answer is C. Let x be the number. Then, you have 3x = 60 + x, which is equivalent to 2x = 60, or x = 30. The number is 30.

Sample practice question: Geometry

If the length, width, and height of a rectangular box measure 1, 3, and 8, respectively, what is the total surface area of the box?

A. 24

B. 35

C. 70

D. 72

E. 144

The correct answer is C. A rectangular box has six faces. The top and bottom faces both have surface areas (8)(3) = 24 for a total of 2(24) = 48. The front and back faces both have surface area (8)(1) = 8, for a total of (2)(8) = 16. The left and right faces both have surface area (3)(1) = 3 for a total of (2)(3) = 6. The surface area of the box is 48 + 16 + 6 = 70.