document.write( "Question 434911: Kelsey drove an average of 50 miles per hour for a 6 hour trip. During the first 4 hours, he drove 47 miles per hour.What was the average speed he drove in miles per hour, for the last 2 hours of his trip? \n" ); document.write( "

Algebra.Com's Answer #301171 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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Kelsey drove an average of 50 miles per hour for a 6 hour trip.
\n" ); document.write( " During the first 4 hours, he drove 47 miles per hour.
\n" ); document.write( "What was the average speed he drove in miles per hour, for the last 2 hours of his trip?
\n" ); document.write( ":
\n" ); document.write( "Let s = his av speed for the last two hrs
\n" ); document.write( ":
\n" ); document.write( "Write a distance equation: dist = speed * time
\n" ); document.write( ":
\n" ); document.write( "Dist at 47 mph + distance at s mph = total distance
\n" ); document.write( "(47*4) + 2s = 50(6)
\n" ); document.write( "188 + 2s = 300
\n" ); document.write( "2s = 300 - 188
\n" ); document.write( "2s = 112
\n" ); document.write( "s = $\"112%2F2\"$
\n" ); document.write( "s = 56 mph for the last two hours
\n" ); document.write( ":
\n" ); document.write( "Check by finding the distance at each speed
\n" ); document.write( "47*4 = 188 mi
\n" ); document.write( "56*2 = 112 mi
\n" ); document.write( "---------------
\n" ); document.write( "Total: 300 mi (6*50) \n" ); document.write( "

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