document.write( "Question 1162297: The access code consists of four digits. The first digit cannot be zero and the last digit must be odd. How many different codes
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\n" ); document.write( "\n" ); document.write( "4 digits total, 1st cannot be 0, last digit must be odd, no repeats allowed
\n" ); document.write( "1st digit cannot be 0, with no repeats allowed leaves (9) options
\n" ); document.write( "2nd Digit no repeats allowed but could be 0 which leaves (9) options again
\n" ); document.write( "3rd Digit no repeats allowed, which leaves (8) options
\n" ); document.write( "4th Digit must be odd, no repeats, 1,3,5,7,9 this leaves (5) options
\n" ); document.write( "Question does not mention if previous digits were odd numbers which would change values quite a bit, but this teacher is straightforward, not into complicate multi answer questions leading me to stick with 5 options for 4th digit
\n" ); document.write( "This leads me to take values and multiply 9x9x8x5=3,240 possible combinations. I'm just not sure if this is right or if I'm missing something. Thanks for your help!
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Algebra.Com's Answer #786074 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "Last digit is one of 5 odd digits 1, 3, 5, 7 or 9.  5 options.\r\n" );
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document.write( "First digit is any of the remaining 9 digits except of 0.  9-1 = 8 options.\r\n" );
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document.write( "    So far, 2 digits of the 10 digits are used; the remaining 8 digits of the 10 digits are still free.\r\n" );
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document.write( "Second digit from the left is any of remaining 8 digits.  8 options.\r\n" );
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document.write( "Third digit from the left is any of remaining 7 digits.  7 options.\r\n" );
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document.write( "In all, there are  5*8*8*7 = 2240 different combinations.\r\n" );
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document.write( "ANSWER.  Under the given conditions,  2240 different codes are possible.\r\n" );
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