document.write( "Question 581228: a car travels at a constant 84 mph in one direction then comes back covering the same distance at a constant 63 mph, what is the average speed? \n" ); document.write( "
Algebra.Com's Answer #371521 by Alan3354(69443)\"\" \"About 
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a car travels at a constant 84 mph in one direction then comes back covering the same distance at a constant 63 mph, what is the average speed?
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\n" ); document.write( "Avg = 2*84*63/(84+63) = 72 mi/hr
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