document.write( "Question 796753: Find how many quarts of 6% butterfat milk and 2% butterfat milk should be mixed to yield 40 quarts of 3% butterfat milk \n" ); document.write( "
Algebra.Com's Answer #481552 by wilft1(217)\"\" \"About 
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two equations for this\r
\n" ); document.write( "\n" ); document.write( "x + y = 40
\n" ); document.write( "number of liters of each type that add up to 40 quarts
\n" ); document.write( "6x + 2y = 3
\n" ); document.write( "how much of each percentage type to make the 3 percent\r
\n" ); document.write( "\n" ); document.write( "start off by multiplying 3 by 40 and putting that answer in the bottom equation\r
\n" ); document.write( "\n" ); document.write( "x + y = 40
\n" ); document.write( "6x + 2y = 120\r
\n" ); document.write( "\n" ); document.write( "now, we are going to solve this using the addition method, we want to get rid of the y then solve for x, so lets multiply the top line by -2\r
\n" ); document.write( "\n" ); document.write( "-2x -2y = -80
\n" ); document.write( "6x + 2y = 120\r
\n" ); document.write( "\n" ); document.write( "add the two lines together\r
\n" ); document.write( "\n" ); document.write( "4x = 40\r
\n" ); document.write( "\n" ); document.write( "divide both sides by 4\r
\n" ); document.write( "\n" ); document.write( "x = 10\r
\n" ); document.write( "\n" ); document.write( "we now know the value of x, plug that number into our original equation and solve for y\r
\n" ); document.write( "\n" ); document.write( "x + y = 40
\n" ); document.write( "6(10) + 2y = 120
\n" ); document.write( ".....................
\n" ); document.write( "x + y = 40
\n" ); document.write( "60 + 2y = 120
\n" ); document.write( "..................
\n" ); document.write( "x + y = 40
\n" ); document.write( "2y = 60
\n" ); document.write( ".................
\n" ); document.write( "x + y = 40
\n" ); document.write( "y = 30
\n" ); document.write( ".............\r
\n" ); document.write( "\n" ); document.write( "x = 1 and y = 30\r
\n" ); document.write( "\n" ); document.write( "we now know that it will take 10 quarts of 6 percent and 30 quarts of 2 percent to make the 3 percent solution
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