各位高手, 请看这一题:
Q21:
k, n, 12, 6, 17
What is the value of n in the list above?
(1) k < n
(2) The median of the numbers in the list is 10.
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.
Answer:
这道题提供的答案是C, 可我认为是E. 原因是以下的K和N值都符合(1)和(2), 然而N不能够被唯一确定. 我想这个CONFUSION来自于我们对MEDIAN的概念缺乏理解.
可能的K/N值:
K=Any value less than 10, N=10, Median = 10.
K=Any value less than 8, N = 8, Median = 8+12/2 = 10.
附录MEDIAN的定义:
Computation of Median
When there is an odd number of numbers, the median is simply the middle number. For example, the median of 2, 4, and 7 is 4.
When there is an even number of numbers, the median is the mean of the two middle numbers. Thus, the median of the numbers 2, 4, 7, 12 is (4+7)/2 = 5.5. | 
