The average (arithmetic mean) of a list of numbers is what percent of the sum of the numbers?

题目

The average (arithmetic mean) of a list of numbers is what percent of the sum of the numbers?
(1) There are 8 numbers in the list.
(2) The sum of the numbers in the list is 100.
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.

答案

这位朋友 你考GRE吧 这个题我选第三个答案,命题（2）和命题（1）是充分的
这个是要求一个数列的算术平均数占数列各数总和的百分之几,这样你就必须知道总和有多少,并且还要知道一共有几个数,根据（1）和（2）可算出答案是百分之十三（四舍五入后的结果）或者百分之十二点五.
加油啊 GRE很难考的