document.write( "Question 384078: If a person travels 40 mph going to city A to B, and 60 mph returning from B to A, what is the average speed of the entire trip? Explain. \r
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\n" ); document.write( "\n" ); document.write( "I told my teacher that the average speed was 50 mph and got marked wrong. Where did I go wrong? \n" ); document.write( "
Algebra.Com's Answer #271885 by mananth(16946)\"\" \"About 
You can put this solution on YOUR website!
lets be practical
\n" ); document.write( "while going to B
\n" ); document.write( "speed = 40 mph
\n" ); document.write( "Assume it takes 1 hour
\n" ); document.write( "so distance = 40 miles
\n" ); document.write( "..
\n" ); document.write( "while returning the speed = 60 mph
\n" ); document.write( "distance = 40
\n" ); document.write( "time= 40/60 = 2/3 hours
\n" ); document.write( "..
\n" ); document.write( "Average speed for the trip = total distance / total time
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\n" ); document.write( "Total distance = 80 miles
\n" ); document.write( "total time= 1+2/3 hours
\n" ); document.write( "=1 2/3
\n" ); document.write( "=5/3 hours
\n" ); document.write( "..
\n" ); document.write( "80/(5/3)
\n" ); document.write( "80*3/5
\n" ); document.write( "=16*3
\n" ); document.write( "=48 mph is the average speed
\n" ); document.write( "..
\n" ); document.write( "does your teacher approve of this logic
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\n" ); document.write( "m.ananth@hotmail.ca\r
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