Mitch: Clarification?

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Mitch: Clarification?

by hoyasj » Fri Feb 17, 2012 6:00 pm
Thanks for the explanation Mitch. Could you please explain why the "bad" to be subtracted out is 5*4. I understand that you have to subtract out the instances where the first and third digits are both 2, but I don't understand why you multiply 5 and 4 to get that.
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Newbie | Next Rank: 10 Posts
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by hoyasj » Fri Feb 17, 2012 6:02 pm
My bad. I posted a new thread instead of replying in the "4 digit" thread. You can ignore this post. I would delete it if I knew how haha.