document.write( "Question 558302: can you explain how to add and subtract a variable fractions.. in many ways\r
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Algebra.Com's Answer #363013 by Edwin McCravy(20060) $\"\"$ $\"About$
You can put this solution on YOUR website!
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document.write( "3 is the \"upper left\"\r\n" );
document.write( "x is the \"lower left\"\r\n" );
document.write( "5 is the \"upper right\"\r\n" );
document.write( "y is the \"lower right\"\r\n" );
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document.write( "Rule:\r\n" );
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document.write( "\"(Upper left times lower right) plus (upper right times lower left) all over\r\n" );
document.write( "(bottom times bottom)\"\r\n" );
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document.write( "Results:\r\n" );
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document.write( "---------------------------------------------------\r\n" );
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document.write( "Same for subtracting, except use \"minus\"\r\n" );
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document.write( " -   \r\n" );
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document.write( "y is the \"upper left\"\r\n" );
document.write( "20 is the \"lower left\"\r\n" );
document.write( "10 is the \"upper right\"\r\n" );
document.write( "x is the \"lower right\"\r\n" );
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document.write( "Rule:\r\n" );
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document.write( "\"(Upper left times lower right) minus (upper right times lower left) all over\r\n" );
document.write( "(bottom times bottom)\"\r\n" );
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document.write( "Results:\r\n" );
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document.write( "Write 10*20 as 200:\r\n" );
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document.write( "Or this second way\r\n" );
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document.write( "Get the least common denominator of xy\r\n" );
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document.write( "1. Divide the first denominator x into the least common\r\n" );
document.write( "denominator xy and get y\r\n" );
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document.write( "2. Multiply the first fraction by unit fraction \r\n" );
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document.write( "3. Divide the second denominator y into the least common \r\n" );
document.write( "denominator xy and get x\r\n" );
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document.write( "4. Multiply second fraction by unit fraction \r\n" );
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document.write( "5. Multiply tops and bottoms in both terms\r\n" );
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document.write( "6. Since the denominators are the same, (xy and yx are the same),\r\n" );
document.write( "   add the numerators and put them over the common denominator \r\n" );
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document.write( "Same for subtracting, except use - for +\r\n" );
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document.write( " - \r\n" );
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document.write( "Get the least common denominator of 20x\r\n" );
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document.write( "1. Divide the first denominator 20 into the least common\r\n" );
document.write( "denominator 20x and get x\r\n" );
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document.write( "2. Multiply the first fraction by unit fraction \r\n" );
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document.write( "· - \r\n" );
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document.write( "3. Divide the second denominator x into the least common \r\n" );
document.write( "denominator 20x and get 20\r\n" );
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document.write( "4. Multiply second fraction by unit fraction \r\n" );
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document.write( "5. Multiply tops and bottoms in both terms\r\n" );
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document.write( " - \r\n" );
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document.write( "6. Since the denominators are the same,\r\n" );
document.write( "   subtract the numerators and put them over the common denominator \r\n" );
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document.write( "Here's a third way to do the first one:\r\n" );
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document.write( "1. Get the least common denominator, xy\r\n" );
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document.write( "2. Multiply both fractions by the unit fraction \r\n" );
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document.write( "3. Cancel left denominators into right numerators in each:\r\n" );
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document.write( "4. Since the denominators are the same, add the numerators and put them \r\n" );
document.write( "   over the common denominator \r\n" );
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document.write( "I'll do the third one by the second method:\r\n" );
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document.write( "( + ) - \r\n" );
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document.write( "Remove the parentheses first\r\n" );
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document.write( "Get the least common denominator of 100y\r\n" );
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document.write( "1. Divide the first denominator 20 into the least common\r\n" );
document.write( "denominator 100y and get 5y\r\n" );
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document.write( "2. Multiply the first fraction by unit fraction \r\n" );
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document.write( "· +  - \r\n" );
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document.write( "3. Divide the second denominator 50 into the least common \r\n" );
document.write( "denominator 100y and get 2y\r\n" );
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document.write( "4. Multiply second fraction by unit fraction \r\n" );
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document.write( "5. Divide the third denominator y into the least common \r\n" );
document.write( "denominator 100y and get 100\r\n" );
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document.write( "6. Multiply third fraction by unit fraction \r\n" );
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document.write( "7. Multiply tops and bottoms in all three terms\r\n" );
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document.write( "8. Since the denominators are the same, combine the numerators and put \r\n" );
document.write( "   them over the common denominator \r\n" );
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document.write( "Edwin
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