1、工商管理硕士入学考试-Data+Sufficiency 及答案解析(总分：100.00，做题时间：90 分钟)一、单项选择题(总题数：1，分数：100.00)Now that youve gotten a little more confident, were going to give you the opportunity to practice “without the training wheels.“ When you want to check your work, you can turn to the solutions at the end. If you arent fam
2、iliar with some of the mathematical concepts, make a note to pay particular attention to that chapter in this book; this practice set covers a wide range of topics tested on the GMAT.On all data sufficiency problems, the answer choices are the same (as youve learned). Weve put them here for your ref
3、erence. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient. EACH statement ALONE is sufficient. Statements (1) a
4、nd (2) TOGETHER are NOT sufficient.（分数：100.00）(1).Is x an integer?(1) x is evenly divisible by .(2) x is evenly divisible by 2. （分数：5.00）A.B.C.D.E.(2).What is the ratio of 2a to b?(1) (2) a+b=5 （分数：5.00）A.B.C.D.E.(3).What is the average of a list of n consecutive integers?(1) The smallest number in
5、the list is 5.(2) n=8（分数：5.00）A.B.C.D.E.(4).Is s=r?(1) s2=r2(2) s is positive.（分数：5.00）A.B.C.D.E.(5).In triangle ABC, what is the length of AB?(1) The length of BC is 5 and the length of AC is 12.(2) Angle C=90.（分数：5.00）A.B.C.D.E.(6).If there are only red, blue, and green marbles in a jar, what is t
6、he ratio of red to blue marbles?(1) The ratio of red to green marbles is 2:3.(2) The ratio of green to blue marbles is 6:5.（分数：5.00）A.B.C.D.E.(7).Over a holiday weekend, a certain car dealer sold off 4 of the cars on its lot. If the cars sold for an average of $6,000 each, how many cars were on the
7、dealers lot at the beginning of the weekend?(1) The average value of the remaining cars on the lot is $5,000.(2) The car dealer made $48,000 in car sales over the weekend.（分数：5.00）A.B.C.D.E.(8).What is the value of ?(1) (2) h=5g （分数：5.00）A.B.C.D.E.(9).Was the price of a certain stereo in March great
8、er than its price in May?(1) The price of the stereo in March was 80 percent of its price in April.(2) The price of the stereo in April was 120 percent of its price in May.（分数：5.00）A.B.C.D.E.(10).If the square root of t is a real number, is the square root of t positive?(1) t0(2) t20（分数：5.00）A.B.C.D
9、.E.(11).If the ratio of brown cars to blue cars in a certain parking lot is 2:3, how many brown cars are in the lot?(1) There are 15 blue cars in the lot.(2) There are 25 cars total in the lot.（分数：5.00）A.B.C.D.E.(12).What is the value of f2-g2?(1) f=-g+8(2) f=g-2（分数：5.00）A.B.C.D.E.(13).A shelf conta
10、ins only books of poetry, short stories, and non-fiction. If Jana draws a book randomly off the shelf, what is the probability that the book will be non-fiction?(1) There are 15 books on the shelf.(2) There are 4 books of poetry and 5 books of short stories on the shelf.（分数：5.00）A.B.C.D.E.(14).A job
11、 opening was posted in September and again in January. In September, the number of applicants for the position was 60. What was the percent change in the number of applicants from September to January?(1) The number of applicants in January was one-third the number of applicants in September.(2) The
12、 number of applicants in January was 20.（分数：5.00）A.B.C.D.E.(15).Is a320?(1) a480(2) a5200（分数：5.00）A.B.C.D.E.(16).What is the length of a side of a certain cube?(1) The volume of the cube is 27.(2) The surface area of the cube is 54.（分数：5.00）A.B.C.D.E.(17).How many prime factors of x are also prime f
13、actors of y?(1) x=30(2) y is a multiple of x.（分数：5.00）A.B.C.D.E.(18).Is m0?(1) (2) m3=64 （分数：5.00）A.B.C.D.E.(19).What is the value of ?(1) (2) v0 （分数：5.00）A.B.C.D.E.(20).There are twenty students in a class, all of whom scored between 0 and 100 on their final exams. If the class average was 85, how
14、many people scored below the average score on the exam?(1) Twelve people in the class scored higher than an 85.(2) The lowest eight scores added up to 640.（分数：5.00）A.B.C.D.E.工商管理硕士入学考试-Data+Sufficiency 答案解析(总分：100.00，做题时间：90 分钟)一、单项选择题(总题数：1，分数：100.00)Now that youve gotten a little more confident, w
15、ere going to give you the opportunity to practice “without the training wheels.“ When you want to check your work, you can turn to the solutions at the end. If you arent familiar with some of the mathematical concepts, make a note to pay particular attention to that chapter in this book; this practi
16、ce set covers a wide range of topics tested on the GMAT.On all data sufficiency problems, the answer choices are the same (as youve learned). Weve put them here for your reference. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient. Statement (2) ALONE is sufficient, but st
17、atement (1) alone is not sufficient. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient. EACH statement ALONE is sufficient. Statements (1) and (2) TOGETHER are NOT sufficient.（分数：100.00）(1).Is x an integer?(1) x is evenly divisible by .(2) x is evenly divisible by 2.
18、 （分数：5.00）A.B. C.D.E.解析：A reminder: The question stem starts with is, so this is a yes or no problem. The first step is to determine whether statement (1) is sufficient, which we can do by trying out some real numbers. If x is 2, which is evenly divisible by , then the answer would be yes. But if x
19、were 1.5, which is also evenly divisible by (2).What is the ratio of 2a to b?(1) (2) a+b=5 （分数：5.00）A. B.C.D.E.解析：Statement (1) says that We are looking for the ratio . If you substitute 2 for (3).What is the average of a list of n consecutive integers?(1) The smallest number in the list is 5.(2) n=
20、8（分数：5.00）A.B.C. D.E.解析：Statement (1) tells us the smallest number, but not how many numbers are in the list. It is not sufficient. Cross off A and D.Statement (2) tells us the value of n, so the question becomes: What is the average of a list of 8 consecutive integers? Since those integers can be l
21、arge, small, or even negative, we have no way to tell what the average is. Statement (2) is not sufficient, so we can eliminate B.Now lets put the two statements together. If we know that 5 is the smallest number in a list of 8 consecutive numbers, then we can easily reconstruct the list and find th
22、e average. So the statements are sufficient when put together, and the answer is C.(4).Is s=r?(1) s2=r2(2) s is positive.（分数：5.00）A.B.C.D.E. 解析：Heres another question that is looking for a yes or no answer. Statement (1) allows for both positive and negative values of both s and r, so we cannot tell
23、 ff s = r. Statement (1) is not sufficient; cross off A and D.Statement (2) just tells us that s is a positive number; we dont know anything about r at all and cannot tell if they are equal; statement (2) alone is not sufficient. Lets eliminate B.What if we combine the two? Statement (2) tells us th
24、at s is positive, but r could still be either positive or negative. We still cannot tell if they are equal, so the answer is E.(5).In triangle ABC, what is the length of AB?(1) The length of BC is 5 and the length of AC is 12.(2) Angle C=90.（分数：5.00）A.B.C. D.E.解析：Statement (1) alone is tempting if y
25、ou are familiar with the right triangles that tend to be tested over and over on the GMAT; however, we dont know from statement (1) that ABC is a right triangle, so we should cross off A and D.With only statement (2), we certainly dont have enough information to answer the question, so B can be elim
26、inated. Together, though, we can complete the picture of a right triangle with two known sides, which means we can figure out the third side using Pythagorean Theorem, and our answer is C. (Since the squares of the two legs add up to 169, the hypotenuse is 13.)(6).If there are only red, blue, and gr
27、een marbles in a jar, what is the ratio of red to blue marbles?(1) The ratio of red to green marbles is 2:3.(2) The ratio of green to blue marbles is 6:5.（分数：5.00）A.B.C. D.E.解析：Statement (1) doesnt give us any information about the number of blue marbles at all. It is not sufficient and we can cross
28、 off A and D.Statement (2) doesnt give us any information about the number of red marbles, so we can eliminate B.When we combine both statements, we have ratios that involve all three colors of marbles. Lets see what happens when we use some real numbers. If there are 6 green marbles, then there are
29、 4 red marbles and 5 blue marbles, making the ratio of red to blue marbles 4:5. If we used a different number for the green marbles-say, 12-we would end up with the same ratio of red to blue. This happens frequently with relative numbers such as ratios, proportions, averages, and probability; keep i
30、n mind that you dont always have to know the actual numbers to know the ratios.Statements (1) and (2) together are sufficient, so the answer is C.(7).Over a holiday weekend, a certain car dealer sold off 4 of the cars on its lot. If the cars sold for an average of $6,000 each, how many cars were on
31、the dealers lot at the beginning of the weekend?(1) The average value of the remaining cars on the lot is $5,000.(2) The car dealer made $48,000 in car sales over the weekend.（分数：5.00）A.B. C.D.E.解析：Given statement (1) alone, we only know average values of both the cars that were sold and the cars th
32、at remained; the dealer could have sold 4 cars and had 1 left, or sold 8 cars and had 2 left, or an infinite number of other options. So we can eliminate A and D.With statement (2), we are able to find the number of cars sold by dividing the total sales by the average price. 48,000/6,000=8, so the d
33、ealer sold 8 cars. Since that is (8).What is the value of ?(1) (2) h=5g （分数：5.00）A.B.C.D.E. 解析：Statement (1) doesnt tell us about g at all, so it is insufficient, and we can cross off A and D. Similarly, statement (2) doesnt tell us about f, so we can eliminate B. If we put the statements together,
34、we have only two equations for our three variables, so we still cannot solve. Since the statements together are not sufficient, the answer is E.(9).Was the price of a certain stereo in March greater than its price in May?(1) The price of the stereo in March was 80 percent of its price in April.(2) T
35、he price of the stereo in April was 120 percent of its price in May.（分数：5.00）A.B.C. D.E.解析：Again, this problem is looking for a yes or no answer. Statement (1) doesnt tell us anything about the May price, so it is not sufficient. We can cross off A and D.Statement (2) doesnt tell us anything about M
36、arch, so it is not sufficient and we can cross off B. With both statements together, we know relative prices, and no matter what numbers we were to assume, the May price ends up slightly higher than the March price. So the answer is definitely no, meaning that both statements together are sufficient
37、, and the answer is C.(10).If the square root of t is a real number, is the square root of t positive?(1) t0(2) t20（分数：5.00）A.B.C.D.E. 解析：This question is looking for a definite yes or no answer. Statement (1) is not sufficient since all it tells us is that t is a positive number. Unless the radical
38、 sign (11).If the ratio of brown cars to blue cars in a certain parking lot is 2:3, how many brown cars are in the lot?(1) There are 15 blue cars in the lot.(2) There are 25 cars total in the lot.（分数：5.00）A.B.C.D. E.解析：When we evaluate statement (1), we can tell that there are 10 brown cars in the l
39、ot, because thats the only number that would give us a ratio of 2:3 if there are 15 blue cars. So we can eliminate B, C, and E.Taking statement (2) alone, we can tell that we have 15 blue and 10 brown cars in the lot, because those are the only numbers that would add up to 25 and give a ratio of 2:3
40、. So either statement is sufficient on its own, which means D is the correct answer.(12).What is the value of f2-g2?(1) f=-g+8(2) f=g-2（分数：5.00）A.B.C. D.E.解析：When we see a quadratic formula like f 2-g2, we almost always want to simplify it to see its parts better. This formula simplifies into (f+g)(
41、f-g), so if we can get values for each of those parenthetical statements, we can calculate the value of the whole. Statement (1) gives the value of f+g when it is rearranged, but doesnt give the value of f-g. We can cross off A and D. Statement (2) gives the opposite: the value of f-g only. So it is
42、 not sufficient on its own-we can cross off B-but the two statements are sufficient together, so C is the correct answer.(13).A shelf contains only books of poetry, short stories, and non-fiction. If Jana draws a book randomly off the shelf, what is the probability that the book will be non-fiction?
43、(1) There are 15 books on the shelf.(2) There are 4 books of poetry and 5 books of short stories on the shelf.（分数：5.00）A.B.C. D.E.解析：Statement (1) doesnt tell us anything about the breakdown of the different types of books, so we dont know how likely Jana is to draw a non-fiction book. Eliminate A a
44、nd D.Statement (2) alone doesnt tell us anything about the number of non-fiction books. So we can eliminate B.Putting the statements together, we can tell that there are 6 non-fiction books on the shelf by subtracting 4 and 5 from 15. Therefore, Jana has a (14).A job opening was posted in September
45、and again in January. In September, the number of applicants for the position was 60. What was the percent change in the number of applicants from September to January?(1) The number of applicants in January was one-third the number of applicants in September.(2) The number of applicants in January
46、was 20.（分数：5.00）A.B.C.D. E.解析：Statement (1) lets us find the number of January applicants (20) and then we can find that the percent change in applicants was 66 3 %, so it is sufficient and we can eliminate B, C, and E. Statement (2) tells us the same thing; it is also sufficient, so we can cross of
47、f A and we are left with D.(15).Is a320?(1) a480(2) a5200（分数：5.00）A.B. C.D.E.解析：Heres another question that is looking for a yes or no answer. Statement (1) allows for both positive and negative values of a, so it is not sufficient, and we can cross off A and D.Statement (2), on the other hand, tell
48、s us that a is positive and must be a value of at least 3. If a3, then the answer to the question stem must always be yes. Therefore, statement (2) is sufficient, and our answer is B.(16).What is the length of a side of a certain cube?(1) The volume of the cube is 27.(2) The surface area of the cube
49、 is 54.（分数：5.00）A.B.C.D. E.解析：Statement (1) tells us that the length of a side of the cube is 3, since the volume is just the length of one side cubed. So we can cross off B, C, and E.Statement (2) is a little trickier, since surface area is generally a less familiar concept. If the surface area of the whole cube is 54, then the area of each one of the 6 faces is 9. That means each side is 3, so statement (2) is also sufficient, and our answer is D.(17).How many prime factors of x are also prime factors of
