<PRE><B>Question 1083743</B>
Alex plans to drive 550 miles from New York to Virginia, driving an average of 50 miles per hour. How many miles per hour faster must he average, while driving, to reduce his total driving time by 1 hour?
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Find the time at 50 mi/hr
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d = r*t
t = d/r
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Then find the speed to take 1 hour less.
d = r*t
r = d/t
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