Adding amounts of time

For a quicker and dispositive explanation, attach an example Excel file that demonstrates the problem(s), following the instructions in the bright yellow banner at the top the webpage.

My guess: the data is text, despite appears and cell format. Use formulas of the form =ISTEXT(A1) to confirm. Looks can be deceiving. And the cell format does not matter.

A1+A2+... might work because in that context, Excel converts text to numbers if Excel can interpret the text as such.

But functions like SUM (and "autosum" is just a shortcut for SUM) purposely ignore text, even if Excel might be able to interpret such values as numbers.


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Aside.... When you finally solve the problem, be sure that the format of cells with time arithmetic is Custom [h]:mm:ss. The squared-bracketed "[h]" ensures that hours greater than 23 are displayed properly.

Try formatting the answer as time (play around with the time formats to show what you need.)