Question 553512
You run 2 kilometers at 10 km/hr and then walk another 2 kilometers at 5 km/hr. What is your average speed for the whole 4-km trip?
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t = 2/10 + 2/5 = 3/5 hr
d = 4 km
r = d/t = 4/(3/5)
= 20/3 km/hr
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