GMAT
题目
A total of 22 men and 26 women were at a party, and the average (arithmetic mean) age of all of the adults at the party was exactly 35 years. If the average age of the men was exactly 38 years, which of the following was closest to the average age, in years, of the women?
解析
可以使用加权平均法：
\[
\frac{\text{权重1}}{\text{权重2}} = \frac{\text{平均数2} - \text{总平均数}}{\text{总平均数} - \text{平均数1}}
\]
举个例子：
\[
\frac{26}{22} = \frac{38 - 35}{35 - \text{平均数1}}
\]
求解“平均数1”，可得结果约为32.46154。
答案：D
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