Most likely you need VBA code to do this.
Let the program captures that you make changes to B or D, and then run
solver automatically.


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Best regards,
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Yongjun CHEN
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"Greg Toews" wrote in message
news:DYCSf.153816$H%4.135827@pd7tw2no...
My equation calculates an interest rate

A1*C1^B1 + A2*C1^B2 + ... + A11*C1^B11 = D1

Columns A, B and D are given. The only unknown is C1 which I want to solve
for. I can do this using solver but I would like something that updates
when columns B and D change.

Can I do this without using the solver or have the solver automatically
update?

Thanks,
G