Q16:

What is the probability that a student randomly selected from a class of 60 students will be a male who has brown hair?

(1) One-half of the students have brown hair.

(2) One-third of the students are males.

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.

请问为什么不选C呢？男生与棕色头发不是独立事件吗？

为什么答案是E呢？

谢谢

現在要求得是男生棕頭髮的人數

條件1說的是班上有一半的人是棕頭髮﹐不知道這一半有所少是男生。

條件2說班上1/3的人是男生﹐這個條件單獨也不可以。 2個條件一起看﹐你還是不

知道1/3的男生中有所少是棕頭髮。