I'm studying statistics and can't seem to solve a question.

It goes like this:

**For the sequence of numbers (1, 1, 3, 4), the variance is:**

(a) 1 (b) 2 (c) 2,25 (d) 2,75 (e)3

(a) 1 (b) 2 (c) 2,25 (d) 2,75 (e)3

The answer is supposed to be letter (b), with the variance being 2, but I can't get to that!

Here's my calculation:

var= (1/N)* [(sum from 1 to N) (xi- average)^2]

Being N the number of elements in the population.

It takes me to this calculation:

N=4

average= (1 + 1 + 3+ 4)/N = 9/4

var=(1/4)* [(1 - (9/4))^2 + (1 - (9/4))^2 + (3 - (9/4))^2 + (4- (9/4))^2]

var=1.68, which is the wrong answer according to this material I have. Anyone can help me solve this, please?