[求助]GWD21-14 如何解答？

The charge for a single room at Hotel P is 25 percent less than the charge for a single room at Hotel R and 10 percent less than the charge for a single room at Hotel G.  The charge for a single room at Hotel R is what percent greater than the charge for a single room at Hotel G ?

A.       15%

B.       20%

C.       40%

D.       50%

E.      150%

Answer: B

我不知道怎样得到20%，请XDJM帮忙解答？谢谢！

我不知道怎样得到20%，请XDJM帮忙解答？谢谢！

根据已知条件有两个方程

（R-P)/R=0.25

(G-P)/G=0.1

求得R=(3/4) P,   G=(10/9)P

问的是（R-G)/R，把上面求得的代进去就是20%

谢谢rosyrosy00 MM。

我把分母的对象搞错了，晕

P=75%R=80%G

R/G-1=80%/75%-1=6/5-1=20%