A certain list consists of 400 different numbers. Is the average (arithmetic mean) of the numbers in the list greater than the median of the numbers in the list?

(1) Of the numbers in the list, 280 are less than the average.

(2) Of the numbers in the list, 30 percent are greater than or equal to the average.


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) and (2) TOGETHER are NOT sufficient.

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题目分析：

（1）    将400个数从小到达排序，所以，中位数为第200个数和第201个数的平均数，又因为条件1中280个数小于平均数，这280个数必然包含中位数，所以可以判断中位数小于平均数。

（2）    30%的数大于或等于平均数，即120个数大于或等于平均数，有280个数小于平均数，同条件1，也能判断。

因此，本题答案为（D），任何一个条件说明均能解题。

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