document.write( "Question 577792: if your on a plane that went 480 miles... and for the first 240 miles you went 60 and the last 240 you did 50mph what was your average mph for the trip\r
\n" ); document.write( "\n" ); document.write( "i took the two mph and dived by 2 to get 55 \n" ); document.write( "
Algebra.Com's Answer #370308 by Alan3354(69443)\"\" \"About 
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if your on a plane that went 480 miles... and for the first 240 miles you went 60 and the last 240 you did 50mph what was your average mph for the trip\r
\n" ); document.write( "\n" ); document.write( "i took the two mph and dived by 2 to get 55
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\n" ); document.write( "Avg = 2*60*50/(60+50) = 6000/110
\n" ); document.write( "=~ 54.55 mi/hr
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\n" ); document.write( "It's not the average of 50 & 60
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\n" ); document.write( "Find the total time:
\n" ); document.write( "t = 240/60 + 240/50 = 4 + 24/5
\n" ); document.write( "t = 44/5 hours
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\n" ); document.write( "r = d/t = 480/(44/5) = 2400/44
\n" ); document.write( "= same answer
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\n" ); document.write( "It's not the avg of 60 & 50 because more time is spent moving at the lower speed.
\n" ); document.write( "If the 2 speeds were 60 & 30, the overall speed = 40, not 45.
\n" ); document.write( "This applies to round-trips, or trips of equal distance only.
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