The problem arises because the numbers cannot be represented precisely in
binary. The only decimal numbers that can be represented precisely in
binary are 0.5, 0.25, 0.125, etc., and multiples thereof. That's why you
may need to round the result of the calculation.
--
David Biddulph

"Scott" wrote in message
...
I may be very sleepy, but try this and tell me why I get "OFF", instead of
"OK":

1. Open a new workbook
2. Enter the following:
Cell A1 =11813.21
B1 =5375.65
C1 =6437.56
D1 =IF(A1-B1-C1=0,"OK","OFF")

3. My result in D1 is "OFF" and it should be "OK"
4. Get a calculator or run it in your smart brain:
11813.21 minus 5375.65 minus 6437.56 = 0 (Big fat Zero!!)

If you play with the first three cells, sometimes it works, sometimes not.
I cannot see why or why not.

If the TRUE statement is performed in a seperate cell, and the IF is done
in
another, I get "OK" when I should.

Is this a flaw in Excel 2003?