document.write( "Question 205489: How many two digit numbers are there whose first digit is larger than the second digit? \n" ); document.write( "
Algebra.Com's Answer #155373 by RAY100(1637)\"\" \"About 
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Visualize the 100\"s chart,,,1-9,,10-19,,20-29,,etc
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\n" ); document.write( "let's start at the 90's row,,,100 is 3 digits so it doesn't count
\n" ); document.write( "90,91,92,93,94,95,96,97,98,,(but not 99) all have less, net 9
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\n" ); document.write( "The 80's row,,,80,81,82,83,84,85,86,87,(but not 88,89),,,net 8
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\n" ); document.write( "The 70's row,,,70,71,72,73,74,75,76,,(but not 77,78,79),,,net 7
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\n" ); document.write( "The 60's row,,60,61,62,63,64,65,( but not 66,67,68,69),,net 6
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\n" ); document.write( "The 50's row,,,50,51,52,53,54,(but not 55,56,57,58,59),,net 5
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\n" ); document.write( "The 40's row,,,40,41,42,43,(but not 44,45,46,47,48,49),,,net 4
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\n" ); document.write( "The 30,s row,,,30,31,32,(but not 33,34,35,36,37,38,39(,,,net 3
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\n" ); document.write( "The 20's row,,,20,21,(but not 22,23,24,25,26,27,28,29),,net 2
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\n" ); document.write( "The 10's row,,,10,(but not 11,12,13,14,15,16,17,18,19),,,net 1
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\n" ); document.write( "The 1's row,,,,none because all single digits,,,,net 0
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\n" ); document.write( "Adding all of those available (9+8+7+6+5+4+3+2+1) = 45
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\n" ); document.write( "of interest, total numbers is 99-9=90,,,therefore half have greater and half equal or less digits. \n" ); document.write( "
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