document.write( "Question 606971: Andy's average driving speed for a 4-hour trip was 45 miles per hour. During the first 3 hours he drove 40 miles per hour. what was his average speed for the last hour of his trip? \n" ); document.write( "
Algebra.Com's Answer #382325 by ankor@dixie-net.com(22740)\"\" \"About 
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Andy's average driving speed for a 4-hour trip was 45 miles per hour.
\n" ); document.write( " During the first 3 hours he drove 40 miles per hour.
\n" ); document.write( " what was his average speed for the last hour of his trip?
\n" ); document.write( ":
\n" ); document.write( "let s = speed on the last hr
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\n" ); document.write( "Write a distance equation; dist = speed * time
\n" ); document.write( "40(3) + 1s = 45(4)
\n" ); document.write( "120 + s = 180
\n" ); document.write( "s = 180-120
\n" ); document.write( "s = 60 mph on the last hr \n" ); document.write( "
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