Which function would you use to round a number to a specified number of digits?

The function used to round a number to a specified number of digits is =ROUND(number, digits). This function allows you to take a numeric value and specify how many decimal places you want it rounded to. For example, if you have a number like 3.14159 and you want to round it to two decimal places, the formula =ROUND(3.14159, 2) would return 3.14.

In this context, the 'number' is the value you want to round, and 'digits' indicates the number of decimal places you want to keep. If you set 'digits' to a positive number, it will round to the right of the decimal point; if you provide a negative number, it will round left of the decimal point.

Other functions listed serve different purposes or do not exist in the same form. For instance, ROUNDUP is a function that specifically rounds a number up, regardless of the value of the next digit, while RND is not a valid Excel function in this context. The DECIMAL function is intended for converting numbers from one base to another and does not perform rounding. Thus, =ROUND is the appropriate function for the task at hand.