PP-DS153

[max999]

On his trip from Alba to Benton, Julio drove the first x miles at an average rate of 50 miles per hour and the remaining distance at an average rate of 60 miles per hour. How long did it take Julio to drive the first x miles?

(1) On this trip, Julio drove for a total of 10 hours and drove a total of 530 miles.

(2) On this trip, it took Julio 4 more hours to drive the first x miles than to drive the remaining distance.

answer:A

[amyliang]

(1) x/50 + (530-x)/60 =10 hr 只有一個未知數 可以解
(2) x/50- (total miles-x)/60=4 hr 二個未知數 不可以解

[max999]

我懂了
謝謝amyliang