<PRE><B>Question 505478</B>
michael drove to a friends house at a rate of 40mi/h. he returned by the same route at a rate of 45mi/h. the driving time for the round trip was 4 h. what is the distance michael traveled?
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To-house DATA:
rate = 40 mph ; time = t hrs ; distance = rt = 40t miles
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From house DATA:
rate = 45 mph ; time = 4-t hrs ; distance = rt = 45(4-t) miles
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Equation:
distance = distance
40t = 45(4-t)
40t = 45*4 - 45t
85t = 45*4
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t = (9/17)4 hrs
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Ans: distance 40t = 40(9/17)4 = 84.71 miles
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Cheers,
Stan H.

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