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You are not logged in. #1 20121013 00:41:40
4 digit no.Two 4digit numbers are to be formed such that the sum of the number is also a 4digit number and in no place the addition is with carrying the number of ways of forming the number under above conditions is #2 20121013 01:01:09
Re: 4 digit no.Hi juan; I am taking it that you mean the sum of the two 4 digit numbers must be a 4 digit number and in no column can there be a carry. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. 