document.write( "Question 282751: Greetings! I need help on this problem which, albeit it looks terribly simple in a first glance, I'm finding difficulty in getting the right solution. the answer to this problem is supposed to be $200. Here goes:
\n" ); document.write( "A dealer bought a phonograph for $160. For how many dollars must he mark it so that after deducting 10% of the marked price, he may sell it at a profit of 12-1/2% of the cost?
\n" ); document.write( "Thanks very much for the help guys! :)
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Algebra.Com's Answer #205275 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
C = Cost of Phonograph = $200.
\n" ); document.write( "M = Marked Up Price of Phonograph = (1+x) * C.
\n" ); document.write( "D = Discounted Selling Price of Phonograph = 1.125 * C.
\n" ); document.write( "D = Discounted Selling Price of Phonograph = .9 * M.\r
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\n" ); document.write( "\n" ); document.write( "Note that M - .1 * M = .9 * M.\r
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\n" ); document.write( "\n" ); document.write( "You have 2 equations that need to be solved simultaneously.\r
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\n" ); document.write( "\n" ); document.write( "They are:\r
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\n" ); document.write( "\n" ); document.write( "D = 1.125 * C and D = .9 * M.\r
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\n" ); document.write( "\n" ); document.write( "Since M = (1+x) * C, Then the equations become:\r
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\n" ); document.write( "\n" ); document.write( "D = 1.125 * C and D = .9 * (1+x) * C.\r
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\n" ); document.write( "\n" ); document.write( "Since both expressions equal to D, then both expressions are equal to each other and you get:\r
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\n" ); document.write( "\n" ); document.write( "1.125 * C = .9 * (1+x) * C\r
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\n" ); document.write( "\n" ); document.write( "Divide C from both sides of this equation to get\r
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\n" ); document.write( "\n" ); document.write( "1.125 = .9 * (1+x)\r
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\n" ); document.write( "\n" ); document.write( "Divide both sides of this equation by .9 and you get:\r
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\n" ); document.write( "\n" ); document.write( "1.25 = 1 + x\r
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\n" ); document.write( "\n" ); document.write( "Subtract 1 from both sides of this equation and you get\r
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\n" ); document.write( "\n" ); document.write( ".25 = x\r
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\n" ); document.write( "\n" ); document.write( "That's your answer.\r
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\n" ); document.write( "\n" ); document.write( "The Price needs to be marked up 25% in order to sell it at a discount of 10% and still make a profit of 12.5%\r
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\n" ); document.write( "\n" ); document.write( "In numbers, this is what happens:\r
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\n" ); document.write( "\n" ); document.write( "The cost is $200.
\n" ); document.write( "the marked price is 1.25 * 200 = $250.
\n" ); document.write( "The discounted price is $250 - .1 * $250 = $250 - $25 = $225.
\n" ); document.write( "The profit is $225 - $200 = $25.
\n" ); document.write( "The profit margin is $25/$200 = .125 = 12.5%.
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