document.write( "Question 892760: A man bought 4 pounds of coffee and 1 pound of butter for a total of $22.25. A month later, the prices had not changed and he bought 5 pounds of coffee and 4 pounds of butter for $34.00. Find the price per pound of both coffee and butter. \n" ); document.write( "
Algebra.Com's Answer #540770 by LinnW(1048)\"\" \"About 
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let c = price of a pound of coffee
\n" ); document.write( " b = price of a pound of butter
\n" ); document.write( "four times the price of one pound of coffee plus 1 times the price
\n" ); document.write( "of a pound of butter equals $22.25
\n" ); document.write( "4*c + 1*b = $22.25
\n" ); document.write( "five times the price of one pound of coffe plus four times the price
\n" ); document.write( "of a pound of butter equals $34.00
\n" ); document.write( "5*c + 4*b = $34.00
\n" ); document.write( "Here are the two equations.
\n" ); document.write( "4c + b = 22.25
\n" ); document.write( "5c + 4b = 34.00
\n" ); document.write( "multiply the top equation by -4
\n" ); document.write( "-16c -4b = -89
\n" ); document.write( "5c +4b = 34
\n" ); document.write( "add the equations
\n" ); document.write( "-11c = -55
\n" ); document.write( "divide by -11
\n" ); document.write( " c = 5
\n" ); document.write( "substitute 5 for c in 5c + 4b = 34
\n" ); document.write( "5(5) + 4b = 34
\n" ); document.write( "25 + 4b = 34
\n" ); document.write( "add -25 to each side
\n" ); document.write( " 4b = 9
\n" ); document.write( "divide by 4
\n" ); document.write( " b = 9/4 = 2.25
\n" ); document.write( "Coffee is $5 per pound and butter is $2.25 per pound \n" ); document.write( "
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