Question 911103
How far can a boy ride his bicycle if he rides away at 10 kilometers per hour and returns at 9 kilometers per hour? The entire trip takes 9.5 hours.
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For a round trip,
Avg speed = 2*10*9/(10+9) = 180/19 km/hr
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d = r*t = (180/19)*9.5 = 90 km Rt
--> 45 km each way