Simple math???

I'm clearly missing something. I have a sheet where I need to add the values in 3 columns (GCards, CC-Fees, Monies) then minus the amounts in PostDiscounts and CC-Amounts giving me the balance in Deposit. But I get an invalid operation error:

Have this working in Excel, but I can't figure it out in Smartsheet.

Any help would be greatly appreciated.

Stephanie

Answers