document.write( "Question 442400: True or False? The number of permutations of two items from a data set is always two times the number of combinations when taking two objects at a time from the same data set. Explain.\r
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Algebra.Com's Answer #305134 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "No, that's true because for instance from the letters\r\n" );
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document.write( "A,B,C,D\r\n" );
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document.write( "The 6 combinations of 2 are\r\n" );
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document.write( "{A,B}, {A,C}, {A,D}, {B,C}, {B,D}, {C,D}\r\n" );
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document.write( "where the order does not matter.\r\n" );
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document.write( "And since every one of those can be made into 2 permutations,\r\n" );
document.write( "where order matters,\r\n" );
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document.write( "{A,B} can be made into the two permutations AB and BA.\r\n" );
document.write( "{A,C} can be made into the two permutations AC and CA.\r\n" );
document.write( "{A,D} can be made into the two permutations AD and DA.\r\n" );
document.write( "{B,C} can be made into the two permutations BC and CB.\r\n" );
document.write( "{B,D} can be made into the two permutations BD and DB.\r\n" );
document.write( "{C,D} can be made into the two permutations CD and DC.\r\n" );
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document.write( "There are 6 combinations (where order does not matter), \r\n" );
document.write( "and 12 permutations (where order does matter), so the\r\n" );
document.write( "proposition is true, not false.\r\n" );
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document.write( "Edwin
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