document.write( "Question 1080159: In an attempt to determine the number of $20 bills in active circulation a bank marked 300 bills with an invisible ink. The bills were then released to the public. In a sample of 1000 bills taken six weeks later, 34 had the invisible mark. Estimate the number of $20 bills in circulation in this area.
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Algebra.Com's Answer #694376 by Theo(13342)\"\" \"About 
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not exactly sure if this is correct, but .....\r
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\n" ); document.write( "\n" ); document.write( "300 bills were marked.\r
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\n" ); document.write( "\n" ); document.write( "out of a sample of 1000, 34 were marked.\r
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\n" ); document.write( "\n" ); document.write( "the ratio of marked bills to sample bills is 34/1000 = .034\r
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\n" ); document.write( "\n" ); document.write( "if that same ratio applies to the population, and you let x represent the population, then you get:\r
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\n" ); document.write( "\n" ); document.write( ".034 * x = 300\r
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\n" ); document.write( "\n" ); document.write( "this says that 300 bills represents .034 of the population.\r
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\n" ); document.write( "\n" ); document.write( "solve for x to get x = 300 / .034 = 8823.529412.\r
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