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歲; total平均35歲;問女生的平均年齡。
我的算法是設女生平均年齡為x
=>(22*38)+(26*x)=48*35
然後每個乘除都硬拚
最後求出答案為(D)32.5
但是這樣花了很多時間
不知道這題有沒有更快的解法
或是計算上有可以先約分等其他小撇步
謝謝!
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※ 編輯: iam1egend (111.80.165.134), 01/07/2015 15:53:12