Tham khảo tài liệu 'wiley the official guide for gmat episode 1 part 6', ngoại ngữ, ngữ pháp tiếng anh phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Problem Solving Answer Explanations end. The points 0 -1 1 0 2 1 and 3 2 are on segment PQ and they divide the segment into three intervals of equal length as shown in the figure below. y 2-- -1 O -1 Q 3 2 1 W 1 0 ị ị t 1 2 3 x P 0 -1 Note that the point 2 1 is twice as far from P 0 -1 as from Q 3 2 and also that it is the distance from Q. The correct answer is B. 40. If n is an integer which of the following must be even A n 1 B n 2 C 2n D 2n 1 E n2 Arithmetic Properties of integers A quick look at the answer choices reveals the expression 2n in answer choice C. 2n is a multiple of 2 and hence must be even. Since only one answer choice can be correct the other answer choices need not be checked. However for completeness A n 1 is odd if n is even and even if n is odd. Therefore it is not true that n 1 must be even. B n 2 is even if n is even and odd if n is odd. Therefore it is not true that n 2 must be even. D 2n 1 is odd whether n is even or odd. Therefore it is not true that 2n 1 must be even. E n2 is even if n is even and odd if n is odd. Therefore it is not true that n2 must be even. The correct answer is C. 41. If 4 is one solution of the equation X2 3x k 10 where k is a constant what is the other solution 42. A B C D E -7 -4 -3 1 6 Algebra Second-degree equations If 4 is one solution of the equation then substitute 4 for x and solve for k. x 3x k 10 4 2 3 4 k 10 16 12 k 10 28 k 10 k -18 Then substitute -18 for k and solve for x. x2 3x -18 10 x2 3x - 28 0 x 7 x - 4 0 x -7 x 4 The correct answer is A. If a c b d ad - bc for all numbers a b c and d then 3 -2 5 4 A -22 B -2 C 2 D 7 E 22 Algebra Simplifying algebraic expressions Using the given pattern with a 3 b 5 c -2 and d 4 gives 12 10 22. 3 -2 5 4 3 4 - 5 -2 The correct answer is E. 199 The Official Guide for GMAT Review 12th Edition 43. 7 1 The sum 8 9 is between A B C D E 1 and 3 2 4 3 and 1 4 1 1 and 14 4 1-4 and 17 1 and 2 2 45. 1- 2-3 A 5 B 5 C 5 5 D 6 E 0 Arithmetic Operations with rational numbers
