Keven wrote:
i need the formula. I know how t o use excel t osum



If you're referring to a generic math problem, and not something specific to
Excel, then I believe the answer is that there is no neat closed form solution
to this problem. You have to solve it iteratively, by searching all possible
solutions, which perhaps is where Excel comes in?

First bear in mind that there may be multiple solutions to this problem so you
have to exhaustively check all possible solutions -- you can't just search until
you find one.

One way to do it is to have your numbers in column A and in column B place a
zero or a one. In column C you multiply A * B. Then you sum column C. If the
sum of C does not match the sum you're trying to match, then you have to change
the 1/0 values in B. The obvious way to do this is to make column B a binary
counter and drive it through all it's possible states with a macro.

This will work nicely for "small" problems. The time required to search the
solution space will of course rise exponentially with the number of elements in
column A.

Good luck...

Bill