SOLUTION: A travels the first 15km at a uniform speed of 20
km/h; the next 75 km at a unifom speed of 50 km/h;ad the last 10Km at a uiform speed of 20Km/h. calculate the average speed for
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-> SOLUTION: A travels the first 15km at a uniform speed of 20
km/h; the next 75 km at a unifom speed of 50 km/h;ad the last 10Km at a uiform speed of 20Km/h. calculate the average speed for
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Question 636542: A travels the first 15km at a uniform speed of 20
km/h; the next 75 km at a unifom speed of 50 km/h;ad the last 10Km at a uiform speed of 20Km/h. calculate the average speed for the entire jourey Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! A travels the first 15km at a uniform speed of 20
km/h; the next 75 km at a unifom speed of 50 km/h;ad the last 10Km at a uiform speed of 20Km/h. calculate the average speed for the entire jourey
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Add the speeds
20 + 50 + 20 = 90
90/3 = 30 km/hr, which is not the right answer.
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Add the distances
15 + 75 + 10 = 100 km
Find the time for each distance
d = r*t
t = d/r
15/20 = 0.75 hours
75/50 = 1.5 hours
10/20 = 0.5 hours
Add the times
= 2.75 hours
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Avg speed = 100/2.75
=~ 36.36 km/hr
