有一题数学题难住了，大家帮我，小三的。

吴林大会 · 发表于 21-10-2013 16:57:03|来自：新加坡

本帖最后由吴林大会于 21-10-2013 16:59 编辑

Bag A，BandC each contains some flour.The mass of flour in Bag B is four times as heavy as the mass of flour in Bag A. The mass of flour in Bag C is half the mass of flour in Bag B.when all the flour in the three bags is packed into packets of 994 g, 6such packets of flour are obtained. If each aram of flour cost $0.03,find the cost of flour in Bag A and BagC.Give your answer in dollars and cents.

答案是：$76.68

但是不知是怎么算出来的，请教各位高手。

BB125 · 发表于 21-10-2013 17:05:40|来自：新加坡

0.03 x 5964 x 3 / 7 = 76.68. (5964 = 994 x 6).

noerk · 发表于 21-10-2013 17:16:10|来自：新加坡

应该这样算：

flour in A + flour in B + flour in C = 994g * 6 = 5964g

5964g * 0.03 = $178.92

Flour in B = 4 * flour in A
Flour in C = 1/2 flour in B = 2 flour in A
So flour in A: S178.92 / (1+4+2) = $25.56
flour in C: 2 * $25.56 = 51.12

So flour A + flour C = $25.56 + 51.12 =$76.68