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krakow
11-23-2004, 05:04 PM
How many 3-digit positive integers are odd and do not contain the digit "5"?


















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288

thebullfighter
11-23-2004, 05:08 PM
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8*9*4 = 288

raj
11-23-2004, 05:14 PM
could u please explain this?

netwizio
11-23-2004, 05:33 PM
For the unit digit possible options are 1,3,7,9 (it must be odd and no 5)=>4 options
For the 10th digit options are 0,1,2,3,4,6,7,8,9=>9 options
For the 100th digit options are 1,2,3,4,6,7,8,9=>8 options

so total no of options are 8*9*4