document.write( "Question 1056978: Elsa drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 10 hours. When Elsa drove home, there was no traffic and the trip only took 7 hours. If her average rate was 18 mph faster on the trip home, how far away does Elsa live from the mountains? \n" ); document.write( "
Algebra.Com's Answer #672049 by ankor@dixie-net.com(22740)![]() ![]() You can put this solution on YOUR website! Elsa drove to the mountains last weekend. \n" ); document.write( " There was heavy traffic on the way there, and the trip took 10 hours. \n" ); document.write( " When Elsa drove home, there was no traffic and the trip only took 7 hours. \n" ); document.write( " If her average rate was 18 mph faster on the trip home, how far away does Elsa live from the mountains? \n" ); document.write( ": \n" ); document.write( "Let s = the speed in heavy traffic \n" ); document.write( "then \n" ); document.write( "(s+18) = normal speed \n" ); document.write( ": \n" ); document.write( "Distance is the same each way, write a dist equation; dist = speed * time \n" ); document.write( "10s = 7(s+18) \n" ); document.write( "10s = 7s + 126 \n" ); document.write( "10s - 7s = 126 \n" ); document.write( "3s = 126 \n" ); document.write( " s = 126/3 \n" ); document.write( " s = 42 mph in heavy traffic and obviously 60 mph on the return \n" ); document.write( ": \n" ); document.write( "Find the distance \n" ); document.write( "10*42 = 420 mi \n" ); document.write( "check the distance \n" ); document.write( "7*60 = 420 mi \n" ); document.write( " |