Question 977296: Mr. Pillot always rides his bicycle to work, and he begims his ride at the same time every day. If he averages 10 miles per hour, he arrives at work 2 minutes late, but, if he averages 15 miles per hour, he arrives 1 minute early. Express your answer as a decimal How many miles does Mr. Pillot ride to work? Express answer as a decimal to the nearest tenth.
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! Mr. Pillot always rides his bicycle to work, and he begims his ride at the same time every day. If he averages 10 miles per hour, he arrives at work 2 minutes late, but, if he averages 15 miles per hour, he arrives 1 minute early. Express your answer as a decimal How many miles does Mr. Pillot ride to work? Express answer as a decimal to the nearest tenth.
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The distance is constant.
d = r*t
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d = r*t --> t = d/r
If he averages 10 miles per hour, he arrives at work 2 minutes late
t+2 = d/10
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if he averages 15 miles per hour, he arrives 1 minute early
t-1 = d/15
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t+2 = d/10
t-1 = d/15
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10t + 20 = d
15t - 15 = d
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10t + 20 = 15d - 15
5d = 35
d = 7 miles
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