Question

If project variance is 9, then standard deviation is equal to:

	a.	81
	b.	0
	c.	9
	d.	3

Answer 1

The project variance is given to be 9.

Now, we know that standard deviation of a set of values is defined as the square root of the variance; and as it is the measure of the deviation of the data set from the mean, so the positive square root is taken.

So, the standard deviation in this case is the positive square root of the variance, which is 9.

So, standard deviation is

ie.

So, the standard deviation is equal to (d) 3.