I am summing up hours in Excel and the sum formula is not working Properly.
For 2 of my 5 cells are adding correctly, but the other 2 when added to the
formula throw the entire thing off.

They are all formatted the same in 13:33 format to measure the # of hours
spent on an activity.

What would the reason be that two of them are not working? (it is almost
like exel is substracting hours when these 2 cells are added)