GWD4-13

[Martina]

Q13:
Company S produces two kinds of stereos: basic and deluxe. Of the stereos produced by Company S last month, 2/3 were basic and the rest were deluxe. If it takes 7/5 as many hours to ptoduce a deluxe stereo as it does to produce a basic stereo, then the number of hours it took to produce the deluxe stereos last month was what fraction of the total number of hours it took to produce all the stereos ?

A. 7/17
B.14/31
C.7/15
D.17/35
E.1/2

ANS: A

搜尋不到這一題　請大家幫我解答一下嚕！！　

[Jessy]

basic須時:deluxe須時=1:7/5
(1/3*7/5)/(2/3 + 1/3*7/5)=7/17

[briandragon]

請問ㄧ下
If it takes 7/5 as many hours to produce a deluxe stereo as
it does to produce a basic stereo

爲何不是~~7/5*B = D

there are 4 times as many A as B
不是4B=A~~嗎??

我被搞糊塗啦~~~

[65kevin]

就如樓上 Jessy 小姐所寫, basic須時 : deluxe須時 = 1 : 7/5, D = 7/5 B, 但單位是所花費的時間.....

[briandragon]

瞭解了

我搞錯了~~~卸卸