document.write( "Question 285734: find the sum of all the four digit number that can be obtained by using the digits 1,2,3,4 once in each. \n" ); document.write( "
Algebra.Com's Answer #207199 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "There are 4! or 24 such numbers. So there are 24 digits in each column.\r\n" );
document.write( "There are the same number of 1's in each column as there are 2's, 3's \r\n" );
document.write( "and 4's. so there are 24÷4 or 6 of each digit in each column.  So each\r\n" );
document.write( "column sums to 6*1+6*2+6*3+6*4 = 6(1+2+3+4) = 6(10) = 60, so the sum is\r\n" );
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document.write( "the sum of the thousands column, which is 60, times 1000 plus \r\n" );
document.write( "the sum of the hundreds column, which is 60, times 100 plus \r\n" );
document.write( "the sum of the tens column, which is 60, times 10 plus\r\n" );
document.write( "the sum of the units column, which is 60. \r\n" );
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document.write( "1000(60) + 100(60) + 10(60) + 60 = 60(1000+100+10+1) = 60(1111)= 66660 \r\n" );
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document.write( "And since there are only 24 of them, you can check just by adding;\r\n" );
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document.write( " 1234\r\n" );
document.write( " 1243\r\n" );
document.write( " 1324\r\n" );
document.write( " 1342\r\n" );
document.write( " 1423\r\n" );
document.write( " 1432\r\n" );
document.write( " 2134\r\n" );
document.write( " 2143\r\n" );
document.write( " 2314\r\n" );
document.write( " 2341\r\n" );
document.write( " 2413\r\n" );
document.write( " 2431\r\n" );
document.write( " 3124\r\n" );
document.write( " 3142\r\n" );
document.write( " 3214\r\n" );
document.write( " 3241\r\n" );
document.write( " 3412\r\n" );
document.write( " 3421\r\n" );
document.write( " 4123\r\n" );
document.write( " 4132\r\n" );
document.write( " 4213\r\n" );
document.write( " 4231\r\n" );
document.write( " 4312\r\n" );
document.write( "+4321\r\n" );
document.write( "-----\r\n" );
document.write( "66660\r\n" );
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document.write( "Edwin
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