document.write( "Question 717935: A family has two cars. The first car has a fuel efficiency of 30 miles per gallon of gas and the second has a fuel efficiency of 20 miles per gallon of gas. During one particular week, the two cars went a combined total of 850 miles, for a total gas consumption of 35 gallons. How many gallons were consumed by each of the two cars that week?\r
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Algebra.Com's Answer #440594 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
Let \"+d+\" = distance in miles the 1st car travels
\n" ); document.write( "\"+850+-+d+\" = distance in miles the 2nd car travels
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\n" ); document.write( "In words:
\n" ); document.write( "( miles ) / ( miles/gallon ) = gallons
\n" ); document.write( "Using this fact:
\n" ); document.write( "\"+d+%2F+30+%2B+%28+850+-+d+%29+%2F+20++=+35+\"
\n" ); document.write( "Multiply both sides by \"+60+\"
\n" ); document.write( "\"+2d+%2B+3%2A%28+850+-+d+%29+=+35%2A60+\"
\n" ); document.write( "\"+2d+%2B+2550+-+3d+=+2100+\"
\n" ); document.write( "\"+-d+=+-450+\"
\n" ); document.write( "\"+d+=+450+\"
\n" ); document.write( "------------
\n" ); document.write( "For 1st car:
\n" ); document.write( "gallons consumed = \"+d%2F30+\"
\n" ); document.write( "gallons consumed = \"+450%2F30+\"
\n" ); document.write( "gallons consumed = \"+15+\"
\n" ); document.write( "For 2nd car:
\n" ); document.write( "gallons consumed = \"+%28+850+-+d+%29%2F20+\"
\n" ); document.write( "gallons consumed = \"+%28+850+-+450+%29%2F20+\"
\n" ); document.write( "gallons consumed = \"+400%2F20+\"
\n" ); document.write( "gallons consumed = \"+20+\"
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\n" ); document.write( "check:
\n" ); document.write( "\"+15+%2B+20+=+35+\"
\n" ); document.write( "OK\r
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