document.write( "Question 957769: there are 5 digits: 1,3,4,7,9. How many positive integers less than 600 can be formed using these 5 digits:
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Algebra.Com's Answer #585813 by Edwin McCravy(20056) $\"\"$ $\"About$

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There are 5 digits: 1,3,4,7,9. How many positive integers less than 600 can be formed using these 5 digits:
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document.write( "There are 5 1-digit numbers.\r\n" );
document.write( "There are 5*5 or 25 2-digit numbers.\r\n" );
document.write( "There are 3*5*5 or 75 3-digit numbers. (we can only choose the\r\n" );
document.write( "first digit as 1,3, or 4 (three ways) for the number to be less that 600. \r\n" );
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document.write( "That's 5+25+75 = 105 ways.\r\n" );
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\n" ); document.write( "(b) if digits cannot be repeated.
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document.write( "There are 5 1-digit numbers.\r\n" );
document.write( "There are 5*4 or 20 2-digit numbers.\r\n" );
document.write( "There are 3*4*3 or 36 3-digit numbers. (we can only choose the\r\n" );
document.write( "first digit as 1,3, or 4 (three ways) for the number to be less that 600. \r\n" );
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document.write( "That's 5+20+36=61 ways.\r\n" );
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document.write( "Edwin

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