document.write( "Question 915878: A grocer wants to mix two kinds of coffee. One kind sells for $2.15 per pound and the other sells for 2.45 per pound. He wants to mix a total of 18 pounds and sell it for $2.30 per pound. How many pounds of each kind should he use in the new mix? \n" ); document.write( "
Algebra.Com's Answer #555801 by AlgebraLady88(44)\"\" \"About 
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This grocer is mixing two kinds of coffee. I always love the smell of coffee!
\n" ); document.write( "We will say that x sells for $2.15 per pound and y sells for $2.45 per pound.\r
\n" ); document.write( "\n" ); document.write( "Altogether there are 18 pounds of coffee he is selling.
\n" ); document.write( "The algebraic equation would be x + y = 18\r
\n" ); document.write( "\n" ); document.write( "At $2.30 per pound, he will make 18 * $2.30 = $ 41.40\r
\n" ); document.write( "\n" ); document.write( "So, how many of the x and y kinds of coffee should he use to make the $2.30 per pound mixture which will net him $41.40?
\n" ); document.write( "The algebraic equation would be 2.15x + 2.45y = 41.40\r
\n" ); document.write( "\n" ); document.write( "We now have two equations :\r
\n" ); document.write( "\n" ); document.write( "x+y = 18
\n" ); document.write( "2.15x + 2.45y = 41.40\r
\n" ); document.write( "\n" ); document.write( "Substituting x= 18 -y in the second equation gives us\r
\n" ); document.write( "\n" ); document.write( "2.15(18-y) + 2.45y = 41.40
\n" ); document.write( "38.70 - 2.15y + 2.45y = 41.40
\n" ); document.write( "38.70 + 0.3y = 41.40
\n" ); document.write( "0.3y = 41.40 - 38.70
\n" ); document.write( "0.3y= 2.70
\n" ); document.write( "y=9\r
\n" ); document.write( "\n" ); document.write( "If y=9, then x= 9 as well. \r
\n" ); document.write( "\n" ); document.write( "So, he will use 9 pounds of the $2.15 per/lb one and another 9 pounds of the $2.45per/lb one.
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