求救一题,大家看看

In a certain voting district, 40 percent of registered voters live in Town A, and the rest live in Town B. In the last election, 70 percent of the registered voters from Town A voted. If equal numbers of registed voters from both town voted, approximately, what percent of the registered voters from Town B voted?

答案是47％

但是不知道如何求出答案的。大家都帮忙看看。谢谢！

假定registered voters是x个,那么

Town A有40%x的registered voters,Town B有the rest也就是60%x的registered voters

Town A的registered voters(40%x)中有70% voted,也就是40%x.70% voted

如果两个towns投票的人数一样,求town B的registered voters里有多少个百分比的人投票了,假设有y percent那就是:40%x.70%=60%x.y%

那么y=47