<PRE><B>Question 835436</B>
You drove for 1 hour at 50 mph with what average speed would you have to drive for the next 3/4 of an hour for your average for the whole trip to be 56 mph
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average = total distance/total time
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56 = (1*50 + (3/4)r)/(1+(3/4))
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56 = (50 + (3/4)r)/(7/4)
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50 + (3/4)r) = (7/4)56 = 98
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(3/4)r = 48
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r = (4/3)(48)
r = 64 mph
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Cheers,
Stan H.
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