Which function is used to add a range of cells?

To add a range of cells in Excel, the function used is SUM. The SUM function is one of the most fundamental and frequently used functions, designed to calculate the total of all numbers within a specified range of cells. For example, =SUM(A1:A5) will add all the values from cell A1 to A5.

• AVERAGE (A) is incorrect; this function calculates the arithmetic mean of a range of cells, not their sum.
• ADD (C) is incorrect; while addition is performed, 'ADD' is not a valid Excel function name for summing a range.
• TOTAL (D) is incorrect; similar to 'ADD', 'TOTAL' is not a recognized Excel function for this purpose.