document.write( "Question 1201969: Without repeating any digits, how many 4-digit numbers can be formed from the numbers {1,2,3,4,5,6}, if you only want the result to be even numbers? \n" ); document.write( "

Algebra.Com's Answer #836570 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Last digit (ones digit) must be one of the three possibilities 2, 4, 6.\r\n" );
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document.write( "1st digit can be any of remaining 5 digits;\r\n" );
document.write( "2nd digit can be any of remaining 4 digits;\r\n" );
document.write( "3rd digit can be any of remaining 3 digits;\r\n" );
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document.write( "In total, there are 3*5*4*3 = 180 such 4-digit numbers.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Another reasoning is THIS:\r
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document.write( "Without restriction on parity, 6*5*4*3 = 360 numbers are possible.\r\n" );
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document.write( "Of them, exactly half, 360/2 = 180, are even numbers.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Two solutions for your satisfaction.\r
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