Question

On a long-distance biking trip, Annike started biking at 7 a.m., and her average speed was 11 miles per hour. Celia started at 8 a.m., and her average speed was 14 miles per hour. At what time will the two bikers have completed the same number of miles?

(Please explain the method you used)

Answer 1

2:40 p.m.

Explanation:

On a long-distance biking trip, Annike started biking at 7 a.m., and her average speed was 11 miles per hour. Celia started at 8 a.m., and her average speed was 14 miles per hour. Therefore, at 2:40 p.m., the two bikers will have completed the same number of miles.

Answer 2

2:40 p.m.

Explanation:

Annike's 11-mile head start is being made up by Celia at the rate of 3 miles per hour. It will take Celia 11/3 = 3 2/3 hours to catch Annike. 3 hours and 40 minutes after 11 a.m. is 2:40 p.m..

Celia and Annike will both have completed 51 1/3 miles at 2:40 p.m..

_____

distance = speed×time

Annike: 11 mph × 4 2/3 h = 51 1/3 mi

Celia: 14 mph × 3 2/3 h = 51 1/3 mi