In this example I am trying to do the following:
A. Subtract row 1 from row 2 Mileage and place results in Sum Cloumn.
B. Any number entered into Trip A Cloumn will automatically be subtracted from Sum Column and displayed as an absolute value into the Trip B Column.

My Challenge/Problem: Whenever the results in the Sum Column displays
as blank, I want it to replace the blank results with the sum of Trip A + Trip B for the row.

Can anyone help? Thanks!



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