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? 男:22 女:26 (total 48人) 已知男生平均38岁; total平均35岁;问女生的平均年龄。 我的算法是设女生平均年龄为x =>(22*38)+(26*x)=48*35 然後每个乘除都硬拚 最後求出答案为(D)32.5 但是这样花了很多时间 不知道这题有没有更快的解法 或是计算上有可以先约分等其他小撇步 谢谢! --

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