document.write( "Question 1091481: How many even three-digit numbers can be formed from the
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Algebra.Com's Answer #706062 by Gentle Phill(18)\"\" \"About 
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#Soln
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\n" ); document.write( "Given d digits:
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\n" ); document.write( "To form even 3-digits without repitition & place of 50:
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\n" ); document.write( "1. Nos must end with either 0,2,4,6
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\n" ); document.write( "2. Nos must not Bgin with 0
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\n" ); document.write( "3. By given rule, 5 must not appear in the middle
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\n" ); document.write( "To ensure coverage for all of the above without contradiction, we must observe D many cases possible bit by bit
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\n" ); document.write( "#Case_1: 0 as unit
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\n" ); document.write( "When 0 is unit, any no. can occupy 1st spot:
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\n" ); document.write( "However:
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\n" ); document.write( "~ When 1,2,3,4 nd 6 re 1st digit, 5 is neva used. We'll've:
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\n" ); document.write( "[5][4][1] = 20
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\n" ); document.write( "Since 0 takes last spot, 1 of 5 nos takes 1st spot and 1 of d remainin 4 nos take 2nd spot
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\n" ); document.write( "~ When 5 occupies 1st spot, we'll've:
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\n" ); document.write( "[1][5][1] = 5
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\n" ); document.write( "#Case_2: Either of 2,4,6 as unit
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\n" ); document.write( "Digit could start with 1,3,5 & any other 2 even not used as unit
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\n" ); document.write( "However:
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\n" ); document.write( "~ When 5 isn't 1st digit, it isn't used at all:
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\n" ); document.write( "[4][4][3] = 48
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\n" ); document.write( "i.e
\n" ); document.write( "[1,3 or any 2 even not used up][remaining 4 nos excluding '5'][2,4 or 6]
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\n" ); document.write( "~ When 5 is used:
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\n" ); document.write( "[1][5][3] = 15
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\n" ); document.write( "[only 5][any other 5 excluding used up evens][2,4,6]
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\n" ); document.write( "Total = 20+5+48+15 = 88
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\n" ); document.write( "Your friend,
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