document.write( "Question 1037600: How many five-digit numbers are as follows? They contain
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document.write( "no duplicate digits. The smallest digit is zero. The largest
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document.write( "digit is nine. The sum of the digits is 20. \n" );
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Algebra.Com's Answer #652227 by Edwin McCravy(20060)![]() ![]() You can put this solution on YOUR website! \r\n" ); document.write( "Since the smallest digit is 0 and the largest \r\n" ); document.write( "digit is 9, and one of them is 0, we just have \r\n" ); document.write( "to come up with three digits between 1 and 8,\r\n" ); document.write( "inclusive, that total the remaining 11, since \r\n" ); document.write( "0+9=9. 1+2+8=11, 1+3+7=11, 1+4+6=11, 2+3+6=11, \r\n" ); document.write( "and 2+4+5=11. \r\n" ); document.write( "\r\n" ); document.write( "We can't put the 0 first, so it's any arrangements\r\n" ); document.write( "of the digits of these five 5-digit numbers that\r\n" ); document.write( "don't have 0 first:\r\n" ); document.write( "\r\n" ); document.write( "10289, 10379, 10469, 20369, 20459\r\n" ); document.write( "\r\n" ); document.write( "For each of these 5 numbers,\r\n" ); document.write( "There are 4 choices of positions to place the 0.\r\n" ); document.write( "For each of those ways, there are 4 choices of positions to \r\n" ); document.write( "place the smallest digit greater than 0.\r\n" ); document.write( "For each of those ways, there are 3 choices of positions to \r\n" ); document.write( "place the next digit in size.\r\n" ); document.write( "For each of those ways, there are 2 choices of positions to \r\n" ); document.write( "place the next to largest digit in size.\r\n" ); document.write( "For each of those ways, there is only 1 choice of position to \r\n" ); document.write( "place the largest digit in size, which is the 9.\r\n" ); document.write( "\r\n" ); document.write( "So there are 5*4*4*3*2*1 = 480 possibilities.\r\n" ); document.write( "\r\n" ); document.write( "Edwin \n" ); document.write( " \n" ); document.write( " |