Robert If I understand what you are trying to do here is the solution.
=IF((A2+B2)<4,(A2+B2-0.21),IF(AND((A2+B2)4,(A2+B2)<8),(A2+B2-0.8),IF(AND((A2+B2)12,(A2+B2)<20),(A2+B2-1.3),"Check")))

The extra () around A2+B2) are what I add - old school way of doing
things.

You need to insert an "AND" function for your 4 and <8, same with you
12 and <20
the "Check" is what I use to tell me if my functions have an error in
them for whatever reason. You will get a check if the Cell equals A2+B2
= 4, 8, 12, 20.
Just substitute the A2 and B2 for the cells you want to substract
from.

If your .21, .8 or 1.3 change - you should put them in a cell and make
a reference to that cell.

When you use an IF(AND) statement and close the "AND" part you will
usually get an "error message" just ignore it then "click" on the "IF"
you need to complete and everything should work.

Hope this helps you out.


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wjohnson
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