In one Column there are Numbers and in other there are num_digits up to which the number to be rounded down. Select cell B6 to make it the active cell. Select Math Trig to open the function drop-down list.
The ROUNDDOWN function in Excel does the opposite of what ROUNDUP does ie.
To round to the nearest multiple use the MROUND function. To round to the nearest multiple use the MROUND function. This function will round down to the nearest Whole number 1. The ROUNDDOWN function is an inbuilt function in Excel under the category of MathTrig Function.