求助1道PREP数学题，请各位不吝赐教啊谢谢

flyfairy019

1.  Alice's take-home pay last year was the same each month, and she saved the same fraction of her take-home pay each month. The total amount of money that she had saved at the end of the year was 3 times the amount of that portion of her monthly take-home pay that she did not save. If all the money that she saved last year was from her take-home pay, what fraction of her take-home pay did she save each month?

A 1/2
B 1/3
C 1/4
D 1/5
E 1/6

题目好绕，不是很看得懂，我的理解Alice每月存的钱应该是3/4啊。。。

flyfairy019

请大家帮忙啊

mjrmjr0213

答案是D，题目中间“The total amount of money that she had saved at the end of the year was 3 times the amount of that portion of her monthly take-home pay that she did not save.” 这句话说的是 他一年存的所有钱是他一个月没存钱数的3倍。 设每月存钱为a,不存钱为b,    12a=3b   ,结论问a/a+b=1/5

flyfairy019

答案是D，题目中间“The total amount of money that she had saved at the end of the year was 3 times the amount of that portion of her monthly take-home pay that she did not save.” 这句话说的是 他一年存的所有钱是他一个月没存钱数的3倍。 设每月存钱为a,不存钱为b,    12a=3b   ,结论问a/a+b=1/5

-- by 会员 mjrmjr0213 (2012/3/22 14:45:56)

原来如此，明白了，谢谢啊。