<PRE><B>Question 1050765</B>
if you want to travel an average of 50/mi per hour on a trip and half of the trip you go 25/mi per hour how fast do you have to travel in the second half 
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2nd half DATA:
rate = 25 mph ; distance = x miles ; time = x/25 hrs
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Final Results::
rate = 50 mph ; distance = 2x miles ; time = (2x)/50 hrs = x/25 hrs
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2nd half DATA:
distance = x miles ; time = (x/25)-(x/25) = 0 ; rate = x/0 = infinity
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After the 1st half at 25 mph there is zero time for the 
2nd half trip if the average rate is to be 50 mph.
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Cheers,
Stan H. 

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