Formula to deduct a cell value

[cletus92]

I need Overtime for 112 hours, So when I add the OT Hours for the individual, it should deduct from the Yellow marked cell, so that I will know, how many more hours are required, pls help

[#2]

What you're asking is (or should be) fairly simple. You could help us help you by being a bit more clear here on what "Enf" and "Apl" and the corresponding numbers represent, all under "Req" --which itself could mean "Required" or "Requested" or, who knows, "Requiem"

[#3]

@cletus92 

If take that literally, why doesn't =Total -SUM(OT Hours) work?