Question 1040310: Olivia traveled 25 miles in 30 minutes, and then she traveled for an additional
20 minutes. If her average speed for the entire trip was 36 miles per hour
(mph), what was her average speed for the final 20 minutes of the trip?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Olivia traveled 25 miles in 30 minutes, and then she traveled for an additional
20 minutes. If her average speed for the entire trip was 36 miles per hour
(mph), what was her average speed for the final 20 minutes of the trip?
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1st leg DATA:: dist = 25 miles ; time = 30 min = (1/2) hour
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2nd leg DATA:: dist = x miles ; time = (1/3) hour
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Average speed = total distance / total time = (25+x)/(5/6 hour) = 30 + (6/5)x mph
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Equation:
(20 + (6/5)x) mph = 36 mph
(6/5)x = 16
x = 80/6 miles (2nd leg distance)
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Ans: 2nd leg speed = dist/time = (80/6)/(1/5) = 400/6 = 66 2/3 mph
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Cheers,
Stan H.
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