document.write( "Question 470481: How many 5-digit numbers can be formed with the first three digits odd and the last two digits even if repetition of digits is allowed? Also, if repetition of digits is not allowed? \n" ); document.write( "

Algebra.Com's Answer #322694 by solver91311(24713) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( "There are 5 even digits and 5 odd digits.\r
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\n" ); document.write( "\n" ); document.write( "So if you allow repetition, there are 5 ways to select the first digit. For each of those ways there are 5 ways to select the second digit. For each of those 25 ways there are 5 ways to select the third digit.\r
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\n" ); document.write( "\n" ); document.write( "So with repetition\r
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\n" ); document.write( "\n" ); document.write( "If repetion not allowed, there are 5 ways to select the first digit. For each of those ways, since you don't allow repetition, there are only 4 ways to select the second digit, and then 3 ways to select the 3rd digit. The 4th digit is now even, so we again have 5 ways, and the last is only 4 ways:\r
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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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