A student wants to calculate the variance of a set of 10 scores. Unfortunately, he doesn't have the raw scores but only has the deviation of each raw score from the mean. Worse yet, he only has 9 of these deviation scores, as listed below. Compute the variance for him.

-5, +11, -4, -2, +7, -8, -6, +1, -3

I have no idea how to do this problem