A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Use the TIME function to add 2 minutes to the value in C1.
In cell B2, use:
=IF(C1="","",C1+TIME(0,2,0))
This keeps B2 blank if C1 is blank; otherwise it returns the date/time in C1 plus 2 minutes.
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