document.write( "Question 986073: How many 3 digit odd numbers can be made from the digits 5,2,1,3,4 ? (without repetition) \n" ); document.write( "
Algebra.Com's Answer #606818 by Edwin McCravy(20056)\"\" \"About 
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How many 3 digit odd numbers can be made from the digits 5,2,1,3,4 ? (without
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document.write( "In problems like this we always choose the most restrictive things first:\r\n" );
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document.write( "The most restrictive thing is the third digit.  Since the number must be odd, we\r\n" );
document.write( "must choose the third digit odd.  There are only 3 ways to choose the third\r\n" );
document.write( "digit odd, 1,3, or 5\r\n" );
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document.write( "That's 3 ways to choose the third digit.\r\n" );
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document.write( "Now let's choose the first digit:\r\n" );
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document.write( "Since we can't repeat the digit we used for the third digit, then for each of\r\n" );
document.write( "those 3 ways to choose the third digit, there are only 4 ways left to choose the\r\n" );
document.write( "first digit.\r\n" );
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document.write( "Therefore the number of ways to choose the third and first digits is 3×4 or 12\r\n" );
document.write( "ways.\r\n" );
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document.write( "Now let's choose the second digit:\r\n" );
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document.write( "Since we can't repeat either of the two digits we used for the third and first\r\n" );
document.write( "digits, then for each of those 12 ways we could choose the third and first\r\n" );
document.write( "digits there are only 3 ways left to choose the second digit. \r\n" );
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document.write( "Therefore the number of ways to choose the three digits is 3×4×3 = 36.\r\n" );
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document.write( "Here's a computer check.  6 rows of 6 each makes 36.\r\n" );
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document.write( "123 125 135 143 145 153 \r\n" );
document.write( "213 215 231 235 241 243 \r\n" );
document.write( "245 251 253 315 321 325 \r\n" );
document.write( "341 345 351 413 415 421 \r\n" );
document.write( "423 425 431 435 451 453 \r\n" );
document.write( "513 521 523 531 541 543 \r\n" );
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document.write( "Edwin
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