document.write( "Question 159912This question is from textbook
\n" ); document.write( ": Suppose you own a card shop. You buy one line of cards at a rate of 4 cards for $5. You plan to sell the cards at a rate of 3 cards for $5. How many cards must you sell in order to make a profit of $100. \n" ); document.write( "
Algebra.Com's Answer #117958 by ankor@dixie-net.com(22740)\"\" \"About 
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Suppose you own a card shop. You buy one line of cards at a rate of 4 cards for $5. You plan to sell the cards at a rate of 3 cards for $5. How many cards must you sell in order to make a profit of $100.
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\n" ); document.write( "Let x = no. of cards required to make $100 profit
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\n" ); document.write( "Cost = (5/4)x
\n" ); document.write( "Revenue = (5/3)x
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\n" ); document.write( " Revenue - cost = Profit
\n" ); document.write( "(5/3)x - (5/4)x = 100
\n" ); document.write( "Multiply equation by 12 to get rid of the denominators; results:
\n" ); document.write( "4(5x) - 3(5x) = 12(100)
\n" ); document.write( "20x - 15x = 1200
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\n" ); document.write( "5x = 1200
\n" ); document.write( "x = \"1200%2F5\"
\n" ); document.write( "x = 240 cards need to be sold
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\n" ); document.write( "Check solution: (5/3)240 - (5/4)240 = 100\r
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