9514 1404 393
Answer:
200 m
Explanation:
Let d represent the length of the track in meters. The relation of interest is ...
time = distance/speed
Then the total time to run and walk back is ...
60 = d/10 + d/5
600 = d + 2d
200 = d . . . . . . . divide by 3
The length of the track is 200 meters.
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200 m in 20 seconds is a world-record time for a woman; a very good time for a man.