A bicyclist travels the first 800 m of a trip with a speed of 10 m/s, the next 500 m with an average speed of 5 m/s and the final 1200 m at a speed of 13 m/s. Find the average speed of
the bicyclist for this trip.

9.18 m/s

Explanation:

The average speed for the entire trip is found total distance/total time. Remember r*t=d, so divide both sides by t and get r = d/t.

So the cyclist went 800+500+1200 m = 2500 m for total distance.

10t =800 leads to t=80 sec

5t=500 leads to t=100 sec

13t = 1200 leads to t = 92.3 sec

total time is 272.3 sec

Average speed for the entire trip is 2500 / 272.3 = 9.18 m/s

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