作者wb (would be!!!!!!!)
看板juniorhigh
标题Re: [问题] 请教一题数学
时间Tue Sep 15 14:26:47 2009
※ 引述《chenemily (天天保持好心情)》之铭言：
: In May Mrs. Lee's earnings were 60 percent of the Lee family's total income.
: In June Mrs. Lee earned 20 percent more than in May.
If the rest of the family's income was the same both months,
then, in June, Mrs. Lee's earnings were approximately
what percent of the Lee family's total income?
我是设Lee全家所得为x,
则五月份Lee单所得 0.6x,其他人的0.4x
六月份Lee单所得为: 0.6x*1.2=0.72x
因为the rest of the family's income was the "same" both months
其余家人的收入 在这两个月中都一样的
所以在六月中其他家人的收入也是0.4x
0.72x+0.4x=1.12x
故答案为 0.72x / 1.12x=64.28%
: 请问哪里可知道 其他所得为0.4x
: 题目只说the rest of the family's income was the same both months
: 为什麽可以推得其他所得为0.4x
: 谢谢
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