document.write( "Question 1110412: A chemical company makes two brands of antifreeze. The first brand is 30% pure antifreeze, and the second brand is 55% pure antifreeze. In order to obtain 120 gallons of a mixture that contains 40% pure antifreeze,how many gallons of each brand of antifreeze must be used. Please help me solve this equation. \n" ); document.write( "

Algebra.Com's Answer #725390 by Cromlix(4381) $\"\"$ $\"About$

You can put this solution on YOUR website!
Hi there,
\n" ); document.write( " Amount.....Percentage....Total
\n" ); document.write( "solution 1...x .........30 ....... 30%x
\n" ); document.write( "solution 2.(120 - x)....55 ....... 55(120 - x)
\n" ); document.write( "solution 3...120........40........ 120(40)\r
\n" ); document.write( "\n" ); document.write( "30%x + 55%(120 - x) = 40%(120)
\n" ); document.write( "0.3x + 0.55(120 - x) = 0.4(120)
\n" ); document.write( "0.3x + 66 - 0.55x = 48
\n" ); document.write( "-0.25x + 66 = 48
\n" ); document.write( "-0.25x = 48 - 66
\n" ); document.write( "-0.25x = - 18
\n" ); document.write( "x = 72
\n" ); document.write( "Solution 1 = 72 gallons
\n" ); document.write( "Solution 2 = 48 gallons
\n" ); document.write( "Proof:
\n" ); document.write( "72 galls of 30% + 48 gallons of 55% = 120 galls of 40%
\n" ); document.write( "0.3(72) + 0.55(48) = 0.4(120)
\n" ); document.write( "21.6 + 26.4 = 48
\n" ); document.write( "Hope this helps :-) \n" ); document.write( "

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