document.write( "Question 1154593: A store reduces the price of a CD player by 20% and then reduces that price by 15%.If the final price of the CD player is $170, what was its original price? \n" ); document.write( "

Algebra.Com's Answer #777117 by ikleyn(52867) $\"\"$ $\"About$

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document.write( "Let the original price be x.\r\n" );
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document.write( "Then after first reduction the price is  \r\n" );
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document.write( "    x - 0.2x = x*(1-0.2) = 0.8x.\r\n" );
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document.write( "Next, after the second reduction, the price is  \r\n" );
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document.write( "    0.8x - 0.15*(0.8x)) = 0.8x*(1-0.15) = 0.8x*0.85 = 0.8*0.85x = 0.68x.\r\n" );
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document.write( "You are given that\r\n" );
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document.write( "    0.68x = 170  dollars.\r\n" );
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document.write( "Hence,  x =  = 250.\r\n" );
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document.write( "ANSWER.  The original price was 250 dollars.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Then you have a problem like this one with the chain of discounts, it is important to understand that the final
\n" ); document.write( "discounted price is the product of the original price and some number of simple factors.\r
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\n" ); document.write( "\n" ); document.write( "You must know what these factors are and how to solve such problems quickly in couple of lines (and a couple of minutes).\r
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\n" ); document.write( "\n" ); document.write( "Learn it from my post.\r
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\n" ); document.write( "\n" ); document.write( "In this problem, the first factor is 1-0.2 = 0.8; the second factor is 1-0.15 = 0.85.\r
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\n" ); document.write( "\n" ); document.write( "So, each factor is the complement of a discount value (presented as decimal) to 1.\r
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