if this is my spreadsheet:

A B C
1 Item 4 bags #n/a

2 Gross Total------------------ #n/a

3 Item 3 Cosmetics 1985.00

4 Item 3 Cosmetics 1500.00

5 Gross Total------------------ 3485.00

6 GRAND TOTAL-------------- "XXXXXXXXXX" <----this is the part that i
want to know. HOw do i use SUMIF to get the grand total of all gross total
automatically (leaving the #n/a values)