document.write( "Question 743389: use each of the digits 4,5,6,7,8 once to create an even number whose tens digit and hundredsndigit add to 12 \n" ); document.write( "
Algebra.Com's Answer #452865 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "There are 2! ways to put the 5 and 7 in 3rd and 4th places.\r\n" );
document.write( "That leaves 3 even digits to put in the other 3 places.\r\n" );
document.write( "That can be done in 3! ways.\r\n" );
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document.write( "So the number of ways to put 5 and 7 in 3rd and 4th places is 2!3!\r\n" );
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document.write( "There are 2!=2 ways to put the 4 and 8 in 3rd and 4th places.\r\n" );
document.write( "Then the 6 must go 5th.  That's 1! way \r\n" );
document.write( "That leaves the 5 and 7 to go in front in 2! ways\r\n" );
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document.write( "So the number of ways to put 4 and 8 in those places is 2!1!2!\r\n" );
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document.write( "So the total number of ways is 2!3!+2!1!2! = 2*6+2*1*2 = 12+4 = 16 ways.\r\n" );
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document.write( "Here are all 16 ways:\r\n" );
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document.write( " 1.  46578\r\n" );
document.write( " 2.  46758\r\n" );
document.write( " 3.  48576\r\n" );
document.write( " 4.  48756\r\n" );
document.write( " 5.  57486\r\n" );
document.write( " 6.  57846\r\n" );
document.write( " 7.  64578\r\n" );
document.write( " 8.  64758\r\n" );
document.write( " 9.  68574\r\n" );
document.write( "10.  68754\r\n" );
document.write( "11.  75486\r\n" );
document.write( "12.  75846\r\n" );
document.write( "13.  84576\r\n" );
document.write( "14.  84756\r\n" );
document.write( "15.  86574\r\n" );
document.write( "16.  86754\r\n" );
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document.write( "Edwin
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