The following data sufficiency problems consist of a question and two statements, labeled (1) and (2), in which certain data are given. You have to decide whether the data given in the statements are sufficient for answering the question. Using the data given in the statements plus your knowledge of mathematics and everyday facts (such as the number of days in July or the meaning of counterclockwise), you must indicate whether
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.

单选题

If b>a, then a is what percent of b?
　 (1) a=4
　 (2) b=4a

A、
A
B、
B
C、
C
D、
D
E、
E

【正确答案】 B

【答案解析】

由条件2可知，a是b的25%；条件1无法计算a、b关系，故本题选B项。

单选题

If n is an integer, and n≠0, is (100+n²) /n a positive integer?
　 (1) n²=25
　 (2) 5n=25

A、
A
B、
B
C、
C
D、
D
E、
E

【正确答案】 B

【答案解析】

条件1无法确定n的值；由条件2可知，n=5，故本题选B项。

单选题

What is the value of integer x?
　 (1) x is a positive integer
　 (2) 17≤x≤18

A、
A
B、
B
C、
C
D、
D
E、
E

【正确答案】 E

【答案解析】

（1）中只能判断x是整数，不能判断x的具体值；（2）中只能判断x的取值范围，不能判断x的具体值；（1）和（2）合起来也不能判断x的具体值，因为x可以等于17或者18。所以本题选E项。

单选题

The hold of a fishing boat contains only cod, haddock, and halibut. If a fish is selected at random from the hold, what is the probability that it will be a halibut or a haddock?
　 (1) There are twice as many halibut as cod in the hold, and twice as many haddock as halibut.
　 (2) Cod account for 1/7 of the fish by number in the hold.

A、
A
B、
B
C、
C
D、
D
E、
E

【正确答案】 D

【答案解析】

将两条件分别代入计算，均可算出概率为6/7，故本题选D项。