document.write( "Question 68270This question is from textbook An Incremental Development
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document.write( ": A truck headed east 2 hours before a bus headed east from the same location. The rate of the bus was 60 mph and the rate of the truck was 40 mph. How long did it take the bus to get 20 miles ahead of the truck? \n" );
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Algebra.Com's Answer #48559 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! A truck headed east 2 hours before a bus headed east from the same location. The rate of the bus was 60 mph and the rate of the truck was 40 mph. How long did it take the bus to get 20 miles ahead of the truck? \n" ); document.write( ": \n" ); document.write( "Let t = time bus is 20 mi ahead of the truck \n" ); document.write( "Let (t+2) = time the truck will 20 mi behind the bus \n" ); document.write( ": \n" ); document.write( "Dist = speed * time: \n" ); document.write( ": \n" ); document.write( "Dist traveled by the truck: 40(t+2) \n" ); document.write( "Dist traveled by the bus: 60t. \n" ); document.write( ": \n" ); document.write( "We know that the bus will have traveled 20 mi more than the truck \n" ); document.write( "60t - 40(t+2) = 20 \n" ); document.write( "60t - 40t - 80 = 20 \n" ); document.write( "20t = 20 + 80 \n" ); document.write( "20t = 100 \n" ); document.write( "t = 100/20 \n" ); document.write( "t = 5 hrs when the bus is 20 mi ahead of the truck \n" ); document.write( ": \n" ); document.write( ": \n" ); document.write( "Check \n" ); document.write( "60(5) - 40(7) = \n" ); document.write( "300 - 280 = 20 mi \n" ); document.write( " \n" ); document.write( " |