Question 414387: A truck covered the distance between two towns at an average speed of 50mph. It moved 65mph for the first 2/5 of the distance before the truck driver stopped for a 1 and a 1/2 hour break. After that, he continued driving for another 195 miles till he arrived at his destination. At what speed was the truck moving during the last 195 miles of the trip? Give your answer in mph.
Answer by lwsshak3(11628)   (Show Source):
You can put this solution on YOUR website! A truck covered the distance between two towns at an average speed of 50mph. It moved 65mph for the first 2/5 of the distance before the truck driver stopped for a 1 and a 1/2 hour break. After that, he continued driving for another 195 miles till he arrived at his destination. At what speed was the truck moving during the last 195 miles of the trip? Give your answer in mph.
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let x=total distance of trip in miles.
s=speed of truck during last 195 miles.
Travel time=distance/speed
Time of travel for entire distance=x/50
x/50=(2/5)x/65+1.5+(3/5)x/s
since 2/5 of the total distance was already covered, the remaining distance was 3/5 of the total distance.
(3/5)x=195
x=5*195/3=325 miles
325/50=.4*325/65+1.5+.6*325/s
195/s=6.5-2-1.5=3
s=195/3=65mph
ans:
During the last 195 miles of the trip, the truck was moving at 65mph.
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