document.write( "Question 1056999: Martina drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 10 hours. When Martina 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 Martina live from the mountains? \n" ); document.write( "

Algebra.Com's Answer #672069 by ikleyn(52802) $\"\"$ $\"About$

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\n" ); document.write( " Martina drove to the mountains last weekend. There was heavy traffic on the way there, and the trip took 10 hours.
\n" ); document.write( "When Martina drove home, there was no traffic and the trip only took 7 hours. If her average rate was 18 mph faster
\n" ); document.write( "on the trip home, how far away does Martina live from the mountains?
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document.write( "Let \"u\" be Martina's average speed on the way from home to mountains (in miles per hour).\r\n" );
document.write( "Then in this way she covered the distance of 10*u miles.\r\n" );
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document.write( "On the way back her average speed was (u+18) mph, according to the condition.\r\n" );
document.write( "And the way back was 7*(u+18) miles long.\r\n" );
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document.write( "Actually, both the ways are equally long, which gives an equation\r\n" );
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document.write( "10u = 7(u+18).\r\n" );
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document.write( "Simplify and solve for u:\r\n" );
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document.write( "10u - 7u = 7*18,\r\n" );
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document.write( "3u = 7*18,\r\n" );
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document.write( "u = 7*6 = 42.\r\n" );
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document.write( "Thus Martina's speed was 42 mph on the way to mountains.\r\n" );
document.write( "Hence, the distance to mountains is 10*42 = 420 miles.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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