Find the variance of 11, 12, 13, 14 and 15.
-
A.
2 -
B.
3 -
C.
(sqrt{2}) -
D.
13
Correct Answer: Option A
Explanation
(Variance (sigma^{2}) = frac{sum (x – mu)^2}{n})
The mean ((mu)) of the data = (frac{11 + 12 + 13 + 14 + 15}{5} = frac{65}{5} = 13)
| (x) | ((x – mu)) | ((x – mu)^{2}) |
| 11 | -2 | 4 |
| 12 | -1 | 1 |
| 13 | 0 | 0 |
| 14 | 1 | 1 |
| 15 | 2 | 4 |
| Total | 10 |
(sigma^{2} = frac{10}{5} = 2)