选择题
2013 AMC 8 Problem 11: Treadmill Time Difference
Ted's grandfather used his treadmill on 3 days this week. He went 2 miles each day. On Monday he jogged at 5 miles per hour. He walked at 3 miles per hour on Wednesday and at 4 miles per hour on Friday. If Grandfather had always walked at 4 miles per hour, he would have spent how many minutes less on the treadmill?
2013 AMC 8 第11题 ：跑步机时差
Ted的祖父本周有3天使用他的跑步机。他每天跑2英里。周一，他以每小时5英里的速度慢跑。他周三以每小时3英里的速度行走，周五以每小时4英里的速度行走。如果爷爷一直以每小时4英里的速度行走，他会在跑步机上少花多少分钟？
A.
1
B.
2
C.
3
D.
4
E.
5