document.write( "Question 1150894: We call a number a descending number if each digit is strictly smaller than the digit that comes before it. For example, 863 is a descending number. How many 3-digit descending numbers are there? \n" ); document.write( "
Algebra.Com's Answer #772464 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "If 2 is in the hundreds place, then there is only 1 three-digit number that is a descending number and it is 210.\r
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\n" ); document.write( "\n" ); document.write( "If 3 is in the hundreds place, then there are three such descending numbers
\n" ); document.write( "310
\n" ); document.write( "320
\n" ); document.write( "321\r
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\n" ); document.write( "\n" ); document.write( "If 4 is in the hundreds place, then we have six descending numbers
\n" ); document.write( "410
\n" ); document.write( "420
\n" ); document.write( "421
\n" ); document.write( "430
\n" ); document.write( "431
\n" ); document.write( "432\r
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\n" ); document.write( "\n" ); document.write( "If 5 is in the hundreds place, then we have ten descending numbers
\n" ); document.write( "510
\n" ); document.write( "520
\n" ); document.write( "521
\n" ); document.write( "530
\n" ); document.write( "531
\n" ); document.write( "532
\n" ); document.write( "540
\n" ); document.write( "541
\n" ); document.write( "542
\n" ); document.write( "543\r
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\n" ); document.write( "\n" ); document.write( "The counts so far are: 1, 3, 6, 10\r
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\n" ); document.write( "\n" ); document.write( "The jump from 1 to 3 is +2
\n" ); document.write( "The jump from 3 to 6 is +3
\n" ); document.write( "The jump from 6 to 10 is +4\r
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\n" ); document.write( "\n" ); document.write( "This pattern continues because we have 15 descending numbers if 6 is the hundreds digit
\n" ); document.write( "610
\n" ); document.write( "620
\n" ); document.write( "621
\n" ); document.write( "630
\n" ); document.write( "631
\n" ); document.write( "632
\n" ); document.write( "640
\n" ); document.write( "641
\n" ); document.write( "642
\n" ); document.write( "643
\n" ); document.write( "650
\n" ); document.write( "651
\n" ); document.write( "652
\n" ); document.write( "653
\n" ); document.write( "654\r
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\n" ); document.write( "\n" ); document.write( "And there are 15+6 = 21 descending numbers with 7 as the hundreds digit, 21+7 = 28 descending numbers with 8 as the hundreds digit, and finally 28+8 = 36 descending numbers with 9 as the hundreds digit.\r
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\n" ); document.write( "\n" ); document.write( "The counts are
\n" ); document.write( "1,3,6,10,15,21,28,36
\n" ); document.write( "Add them up
\n" ); document.write( "1+3+6+10+15+21+28+36 = 120\r
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\n" ); document.write( "\n" ); document.write( "Answer: 120\r
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\n" ); document.write( "\n" ); document.write( "Below is a pastebin link of all 120 three-digit descending numbers
\n" ); document.write( "https://pastebin.com/WqFYtfc4
\n" ); document.write( "This is to avoid adding further clutter to this current page.
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