A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
If you are using =C36+F36 in cell H36, use below instead
=SUM(C36,F36)
This will return a zero.
If you want to return a blank in case either of the cells is blank, then use:
=IF(OR(C36="",F36=""),"",SUM(C36,F36))
Regards,
Amit Tandon