document.write( "Question 162810: A car went 4 miles up a hill at 10 miles per hour and back down the same hill 20 miles per hour. What was the average speed for the round trip? \n" ); document.write( "
Algebra.Com's Answer #120014 by checkley77(12844)\"\" \"About 
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D=RT OR D/R=T
\n" ); document.write( "4/10+4/20=.4+.2=.6 IS THE TIME FOR THE TOTAL TRIP.
\n" ); document.write( "8/.6=13.33 MPH IS THE AVERAGE SPEED.
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