Question

What is the variance of the data set? 8, 9, 10, 16, 17

Answer 1

Mean = (8 + 9 + 10 + 16 + 17) / 5 = 60/5 = 12.

x - mean:

8 - 12 = -4,  -4² = 16

9 - 12 = -3,  -3² = 9

10 - 12 = -2,  -2² = 4

16- 12 = 4,  4² = 16

17- 12 = -5,  -5² = 25

Sum of the squares =   16 + 9 + 4 + 16 +25 = 70

Variance = 70/5 = 14

Variance = 14