I know what I want to do but don't know how to get it done....any help
appritated.

I need to compare 2 cells and if BOTH of those cells are empty I need a "-"
in the cell, otherwise if one or both have a value I want to perform a
calculation. I have the following but it's not working. I think I just need
to know the correct symbol to use when comparing:

=(IF(E11 AND F11 = " ","-",G10+E11-F11))

HELP?