document.write( "Question 1065991: Call an integer dangerous if no two of its digits are equal and no digit is 2. Call an integer sexy if all its digits are odd. How many four-digit integers are either sexy or dangerous? \n" ); document.write( "
Algebra.Com's Answer #681164 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
The 1st digit must exclude 0 or 2, so
\n" ); document.write( "there are 8 choices for the 1st digit
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\n" ); document.write( "The 2nd 2nd digit excludes the 1st digit
\n" ); document.write( "and 2, so there are 8 choices
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\n" ); document.write( "The 3rd digit excludes 1st and 2nd digits
\n" ); document.write( "and 2, so there are 7 choices
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\n" ); document.write( "There are 6 choices for the 4th digit
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\n" ); document.write( "There are \"+8%2A8%2A7%2A6+=+2688+\"- dangerous numbers
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\n" ); document.write( "So there are no overlaps with sexy integers
\n" ); document.write( "count the number of dangerous integers
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\n" ); document.write( "5 choices for the 1st ( dangerous integer ) digit
\n" ); document.write( "are odd
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\n" ); document.write( "4 choices for the 2nd digit are odd
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\n" ); document.write( "3 choices the the 3rd are odd
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\n" ); document.write( "2 choices for the 4th are odd
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\n" ); document.write( "There are \"+5%2A4%2A3%2A2+=+120+\" dangerous numbers that are sexy
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\n" ); document.write( "\"+2688+-+120+=+2568+\"
\n" ); document.write( "There are 2568 dangerous numbers that are NOT sexy
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\n" ); document.write( "There are \"+5%2A5%2A5%2A5+=+625+\" sexy numbers
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\n" ); document.write( "There are \"+2568+%2B+625+=+3193+\" 4 digit numbers
\n" ); document.write( "that are EITHER sexy or dangerous
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\n" ); document.write( "Definitely get a 2nd opinion on this!!!
\n" ); document.write( "I could easily be missing something\r
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