Running at an average rate of 5 meters per second, a sprinter ran to the end of a track. The sprinter then jogged back to the starting point at an average rate of 4 meters per second. The total time for the sprint and the jog back was 2 minutes 15 seconds. Find the length of the track.
A)310 meters
B)315 meters
C)300 meters
D)290 meters
E)320 meters

Question

Quizplus · Accepted Answer

Let the length of the track be x meters.
Then, time taken to run to the end of the track = x/5 seconds
Time taken to jog back to the starting point = x/4 seconds
Total time taken = x/5 + x/4 = (9x/20) seconds

Since the total time taken is 2 minutes 15 seconds = 135 seconds, we have:

(9x/20) = 135
x = 300

Therefore, the length of the track is 300 meters.

Running at an Average Rate of 5 Meters Per Second