On Feb 18, 9:01*am, Karen wrote:
I am working on a spreadsheet which calcualtes a decrease
in base wages, which is working fine: A1*(1-A2)= X or
$15.00 *(1-8%) = $13.80. *Howeever, when I work the formula
in reverse, I don't get my original number: $13.80 *
8% = $14.90. Why is that?

Your algebra is wrong. If A1*(1-A2) = X, then A1 = X / (1-A2), not A1
= X * (1+A2), which is what you really did (that is, you did 13.80*
(1+8%), not 13.80*8%).

For example, 13.80/(1-8%) does indeed equal 15.

Note: Due to anomalies of computer binary arithmetic, it might not
always be __exactly__ equal.