document.write( "Question 1192828: How many 4-digit numbers can be formed by using 2, 4, 6, 8, 10,12 without repetition of digits? if it is a combination. \n" ); document.write( "
Algebra.Com's Answer #824767 by Edwin McCravy(20056)\"\" \"About 
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document.write( "Case 1: Using only 2,4,6,8\r\n" );
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document.write( "There are P(4,4) = (4)(3)(2)(1) = 4! = 24 ways to arrange them.\r\n" );
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document.write( "Case 2: Using 10, and 2 others digits from 2,4,6,8\r\n" );
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document.write( "There are 3 basic ways for case 2: \r\n" );
document.write( "10 _ _,   _ 10 _, and _ _ 10\r\n" );
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document.write( "For each of those 3, there are P(4,2) = (4)(3) = 12 ways to arrange\r\n" );
document.write( "two others in the 2 blanks.\r\n" );
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document.write( "So that's (3)(12) = 36 ways.\r\n" );
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document.write( "Case 3: Using 12, and 2 others digits from 2,4,6,8.\r\n" );
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document.write( "That's the same answer as Case 2, also 36 ways.\r\n" );
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document.write( "Case 4:  Using both 10 and 12.\r\n" );
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document.write( "Only 2 ways, 1012 and 1210.\r\n" );
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document.write( "Total for all 4 cases: 24+36+36+2 = 98 ways.\r\n" );
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document.write( "Edwin
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