GMAT không phải là bài thi kiểm tra trình độ tiếng Anh như TOEFL, IELTS hay bài thi kiểm tra trí thông minh mà GMAT là bài kiểm tra khả năng phân tích đọc suy luận trong các chủ đề về định lượng và vấn đáp. Để đạt được điểm cao trong kỳ thi, các học viên phải nắm rõ được cấu trúc, chỉ dẫn và hiểu được ý của người ra đề thi là điều cấp bách! Và vì GMAT là bài kiểm tra có áp lực về thời gian làm bài (thí sinh có thời gian ít hơn 2. | ------------------------------ QUANTITATIVE PRACTICE TEST ---------------------------------------- 20. a. Solve for x first. Since 3x 1 81 and 81 is 34 make an easier equation just based on the exponents. This would be x 1 4. x 3. Therefore x - 1 3 - 1 2. 21. b. Use the counting principle Take the number of choices you have for each course and multiply them together to get the total possible combinations. x X y 1 X z. Use the distributive property to simplify to xyz xz. 22. c. For this type of problem substitute the values you are given for x and y. In this case x 2 and y 3. The expression becomes 2 2 3 2. Using the order of operations perform the operation within the parentheses first and then the exponent. 2 5 2 2 25 . Multiply to get 50. 23. d. Statement I is an example of the associative property of multiplication and statement III is an example of the distributive property. These properties will hold for any real numbers that are substituted into them. Statement II is not a property of real numbers and may be true for certain numbers but not for every real number. 24. b. Since y 6x multiplying each side of the equation results in 6y 6 6x . Recall that since 6 61 6x X 61 6x 1 by the laws of exponents. 25. b. Remember that consecutive odd integers are numbers that are two apart in order like 11 13 and 15. The average of six consecutive odd integers will be an even number. If x 2 is the average then this value will be at the middle of the integers if they are arranged in order. Therefore the three consecutive odd integers smaller than this are expressed as x 1 x - 1 and x - 3 in descending order. The smallest odd integer is x - 3. 26. a. Write an equation for the question by translating the first sentence. The product of a and b is ab and 11 more than twice the sum of a and b translates to 2 a b 11. The equation is ab 2 a b 11. Substitute 7 for b. 7a 2 a 7 11. This simplifies to 7a 2a 14 11 by the distributive property and then becomes 7a 2a 25. Subtract 2a from