document.write( "Question 1207766: A 20-pound bag of Economy brand cement mix contains 25% cement and 75% sand. How much pure cement must be added to produce a cement mix that is 40% cement?\r
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\n" ); document.write( "\n" ); document.write( "I came up with this equation:\r
\n" ); document.write( "\n" ); document.write( "0.25x + 0.75x = 0.40(2x)\r
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Algebra.Com's Answer #845822 by josgarithmetic(39617) $\"\"$ $\"About$

You can put this solution on YOUR website!
Fairly common two part mixture problem Sand is the filler. Concentration can emphasize the cement.\r
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\n" ); document.write( "\n" ); document.write( "Maybe but often not necessary, try this:
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document.write( "                   FRACTION      AMOUNT        AMT. Only Cement\r\n" );
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document.write( "The Bag             0.25          20           0.25*20\r\n" );
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document.write( "Pure Cement        1.00           x          (1)(x)\r\n" );
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document.write( "TOTAL             9.40          x+20          x+(0.25)(20)\r\n" );
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\n" ); document.write( "Equation to form should be obvious.\r
\n" ); document.write( "\n" ); document.write( " $\"%28x%2B%280.25%29%2820%29%29%2F%28x%2B20%29=0.40\"$ \r
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