138。 At a loading dock, each worker on the night crew loaded 3/4 as many boxes as each worker on the day crew. If the night crew has 4/5 as many workers as the day crew, what fraction of all the boxes loaded by the two crews did the day crew load?

谢拉

我们不妨设夜里的每人装载量为n,白天的为d. 那么有 n=(3/4)d

设人数为N,则有Nn=(4/5)Nd

那么夜里的总装载量就为d*(3/5)Nd,而白天的为d*Nd.

接下来算白天的占总共的比例自然很好算了~

好久没做数学了,过来凑个热闹~