PREP-T2-PS-Q88

[GC06]

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?

(A) 64%
(B) 68%
(C) 72%
(D) 76%
(E) 80%

答案是A

我的算法是 Mrs. Lee's earnings 五月=0.6T
所以六月增加20%=1.2*0.6T =0.72T
這樣答案是C 請問我思路哪裡錯誤
感謝

[Enriqueta]

假設5月全家的收入是L
in May, Mrs. Lee's earnings= 0.6L
in June, Mrs. Lee's earnings= 1.2 *0.6L = 0.72L
in both May and June, the rest of the family's income= 0.4L

0.72L/ (0.72L+0.4L)= 72/112= 0.64

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?

(A) 64%
(B) 68%
(C) 72%
(D) 76%
(E) 80%

答案是A

我的算法是 Mrs. Lee's earnings 五月=0.6T
所以六月增加20%=1.2*0.6T =0.72T
這樣答案是C 請問我思路哪裡錯誤
感謝

[aqboy[origen]]

in both May and June, the rest of the family's income= 0.4L

0.72L/ (0.72L+0.4L)= 72/112= 0.64

這邊看不董@@ 為甚麼是0.4L+0.72L???

[Huang Hsin-Yi]

mary's june income/ total in june

-->mary's june income/ mary's june income+ the rest of family income

[aqboy[origen]]

終於看懂了@@感謝