CDers帮忙翻译下，没有看懂题意，谢谢。 2

一生涯凡人也

20. If a motorist had driven 1 hour longer on a certain day and at an average rate of 5 miles per hour faster, he would have covered 70 more miles than he actually did. How many more miles would he have covered than he actually did if he had driven 2 hours longer and at an average rate of 10 miles per hour faster on that day?
(A) 100(B) 120(C) 140
(D) 150(E) 160
CDers帮忙翻译下，没有看懂题意，谢谢。

lpchen0613

答案选什么，是不是选C

一生涯凡人也

答案是D。

沧月小鱼

Assuming:
time +1 hr
rate +5 m/hr
distance +70m
(r+5)*(t+1)=d+70
ask for:
newly increased distance+d=(r+10)(t+2)
d - distance on that certain day
r - rate on that certain day
t- time on that certain day

一生涯凡人也

十分感谢，但还是不会算。