document.write( "Question 518399: A TRUCK DRIVER TRAVELED AT 40mph for the first part of a 646-miletrip, then increased his speed to 58 mph for the rest of the trip. the entire trip took 13 hours. how many hours are traveled at 58 mph? \n" ); document.write( "
Algebra.Com's Answer #345155 by Maths68(1474)\"\" \"About 
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\n" ); document.write( "He Drove at 40mph = t hours
\n" ); document.write( "He Drove at 58mph = 13-t hours
\n" ); document.write( "Distance he covered at 40mph = 40t
\n" ); document.write( "Distance he covered at 50mph = 50(13-t)
\n" ); document.write( "Total Distance covered = 646\r
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\n" ); document.write( "\n" ); document.write( "Distance he covered at 40mph + Distance he covered at 50mph = Total Distance covered
\n" ); document.write( "40t+50(13-t)=646
\n" ); document.write( "40t+650-50t=646
\n" ); document.write( "40t-50t=646-650
\n" ); document.write( "-10t=-4
\n" ); document.write( "-10t/t=-4/-10
\n" ); document.write( "t=4/10
\n" ); document.write( "t=2/5 \r
\n" ); document.write( "\n" ); document.write( "He Drove at 40mph = t = 2/5 hours or 24 minutes
\n" ); document.write( "He Drove at 58mph = 13-t = 13-(2/5)=(65-2)/5=63/5= 5hours 3/5 minutes (36 minutes)\r
\n" ); document.write( "\n" ); document.write( "Check
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\n" ); document.write( "Distance he covered at 40mph = 40t = 40 * 2/5 = 8*2=16 miles
\n" ); document.write( "Distance he covered at 50mph = 50 * 63/5 = 10*63=630 miles
\n" ); document.write( "Sum both distances = 16+630=646 miles
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