SOLUTION: A tourist bus travels 120 kilometers to its destination. The average speed returning is twice the average speed going and the time for a round trip is 5 hours. What is the average

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Question 351102: A tourist bus travels 120 kilometers to its destination. The average speed returning is twice the average speed going and the time for a round trip is 5 hours. What is the average speed of the bus in going to its destination? Thank you so much.
Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website!
Hi,
*Note: distance to and from the same. D = r*t
Let r be the speed and t the time it takes to travel to its destination
Return speed is then 2*r and the time left for that trip is (5hr-t)
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Question states:
going to destination
r*t = 120km
r = 120km/t
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returning from destination (substitute and solve for t

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simplify and solve:
240(5hr-t) = 120t
1200hr - 240t = 120t
1200hr = 360t
3 1/3 hr = t
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Finding rate going to destination
r*(10hr/3)= 120mi
r = 36 mi/hr