document.write( "Question 813178: I got this only math homework and I really need help solving it. This is what it says: Bryan bought a new battery-gasoline hybrid car. On a trip the car ran exclusively on its battery for the first 40 miles, and then ran exclusively on gasoline, using gasoline at a rate of .02 gallons per mile. On the whole trip he averaged 60 miles per gallon. How long was the trip in miles? \n" ); document.write( "

Algebra.Com's Answer #489517 by Edwin McCravy(20065) $\"\"$ $\"About$

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I got this only math homework and I really need help solving it. This is what it says: Bryan bought a new battery-gasoline hybrid car. On a trip the car ran exclusively on its battery for the first 40 miles, and then ran exclusively on gasoline, using gasoline at a rate of .02 gallons per mile. On the whole trip he averaged 60 miles per gallon. How long was the trip in miles?
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document.write( "Let x = the answer, the number of miles long the trip was.\r\n" );
document.write( "Then x-40 = the number of miles the car went on gasoline.\r\n" );
document.write( "Then .02(x-40) = the number of gallons used on the whole trip\r\n" );
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document.write( "     x miles            60 miles\r\n" );
document.write( "-----------------  =  ------------ \r\n" );
document.write( ".02(x-40) gallons       1 gallon\r\n" );
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document.write( "Cross multiply\r\n" );
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document.write( "      60(.02)(x-40) = x\r\n" );
document.write( "      \r\n" );
document.write( "          1.2(x-40) = x\r\n" );
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document.write( "           1.2x-48 = x\r\n" );
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document.write( "               .2x = 48\r\n" );
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document.write( "                 x = 240\r\n" );
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document.write( "240 miles.\r\n" );
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document.write( "Edwin

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