Q1) What does this part of the formula do F4<""
The formula is checking whethere cell F4 is blank or not. '<' means not
eaqual to. In short if F4 is not blank, the formula will execute first part
in IF() otherwise the later part in IF().

Q2) I only want the formula to calculate if there is a value in either F4 or
G4 not both.
Replace F4<"" with OR(F4<"",G4<"")

This will ensure that there should be value in one of the cells.


--
Pranav Vaidya
VBA Developer
PN, MH-India
If you think my answer is useful, please rate this post as an ANSWER!!


"David" wrote:

I would be be very grateful if somone could help me with the following
formula problem I have.
H4=IF(F4<"",PI()*E4/(6.5*F4),PI()*E4/G4)
Q1) What does this part of the formula do F4<""
Q2) I only want the formula to calculate if there is a value in either F4
or G4 not both.