document.write( "Question 1207675: Hi
\n" ); document.write( "Sarah spent 3/8 of her allowance on food and 1/3 of the remainder on clothes. Then she shares the rest of her allowance equally with her sisters such that each of them received 1/12 of her total allowance. \r
\n" ); document.write( "\n" ); document.write( "How many sisters does she have.
\n" ); document.write( "Given that they each received $208 dollars, how much does Sarah spend on clothes.
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Algebra.Com's Answer #845881 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "There are more than 1 answer, because we are not given the number of sisters.\r\n" );
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document.write( "Starts with T.\r\n" );
document.write( "Spends (3/8)T on food.  Has (5/8)T left.\r\n" );
document.write( "Spends (1/3)(5/8)T = (5/24)T on clothes. Has (5/8)T-(5/24)T = (5/12)T left.\r\n" );
document.write( "Shares equally with N sisters.\r\n" );
document.write( "Since it says she shares equally with N sisters, that doesn't mean she gives\r\n" );
document.write( "it all to them. She gives each of the siblings, including herself, (5/12)T/(N+1),\r\n" );
document.write( "which is 208.\r\n" );
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document.write( "So we have the Diophantine equation:\r\n" );
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document.write( "\"%28expr%285%2F12%29T%29%2F%28N%2B1%29\"\"%22%22=%22%22\"\"208\"\r\n" );
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document.write( "\"expr%285%2F12%29T\"\"%22%22=%22%22\"\"208%28N%2B1%29\"\r\n" );
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document.write( "\"5T\"\"%22%22=%22%22\"\"2496%28N%2B1%29\"\r\n" );
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document.write( "\"5T\"\"%22%22=%22%22\"\"2496N%2B2496\"\r\n" );
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document.write( "Here is the way I was taught to solve first degree Diophantine equations.\r\n" );
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document.write( "Write each number in terms of its nearest multiple of the smallest coefficient\r\n" );
document.write( "in absolute value. So write each 2496 as 2495+1 (because 2495 is the nearest\r\n" );
document.write( "multiple of 5.\r\n" );
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document.write( "\"5T\"\"%22%22=%22%22\"\"%282495%2B1%29N%2B%282495%2B1%29\"\r\n" );
document.write( "\"5T\"\"%22%22=%22%22\"\"2495N%2BN%2B2495%2B1\"\r\n" );
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document.write( "Divide through by 5\r\n" );
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document.write( "\"T\"\"%22%22=%22%22\"\"499N%2BN%2F5%2B499%2B1%2F5\"\r\n" );
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document.write( "Isolate the fraction terms:\r\n" );
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document.write( "\"T-499N-499\"\"%22%22=%22%22\"\"N%2F5%2B1%2F5\"\r\n" );
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document.write( "The left side is an integer, so the right side is also an integer.\r\n" );
document.write( "Let that integer be A.\r\n" );
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document.write( "\"N%2F5%2B1%2F5\"\"%22%22=%22%22\"\"A\"\r\n" );
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document.write( "\"N%2B1\"\"%22%22=%22%22\"\"5A\"\r\n" );
document.write( "\"N\"\"%22%22=%22%22\"\"5A-1\", the number of sisters\r\n" );
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document.write( "Substitute in\r\n" );
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document.write( "\"5T\"\"%22%22=%22%22\"\"2496N%2B2496\"\r\n" );
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document.write( "\"5T\"\"%22%22=%22%22\"\"2496%285A-1%29%2B2496\"\r\n" );
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document.write( "\"5T\"\"%22%22=%22%22\"\"12480A-2496%2B2496\"\r\n" );
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document.write( "\"5T\"\"%22%22=%22%22\"\"12480A\"\r\n" );
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document.write( "\"T\"\"%22%22=%22%22\"\"2496A\"\r\n" );
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document.write( "She spent \"expr%285%2F24%29T\"\"%22%22=%22%22\"\"expr%285%2F24%29%282496A%29\"\"%22%22=%22%22\"\"520A\" on clothes\r\n" );
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document.write( "A   Number of sisters  Spent on clothes\r\n" );
document.write( "          5A-1              520A\r\n" );
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document.write( "1           4                520\r\n" );
document.write( "2           9               1040\r\n" );
document.write( "3          14               1560\r\n" );
document.write( "4          19               2080\r\n" );
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document.write( "There are multiple answers.\r\n" );
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document.write( "Edwin
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