To add up the sum total in Google spreadsheet you should create an empty cell below the list of items you wish to add up in the column.
ie,
A1 = 33
A2 = 23
A3 = 11
A4 = (Empty cell where you type this:
=sum(A1:A3)
then press enter,
A4 will now show you the sum total of cells A1 – A3 which should equal
A4 = 67
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