Calculate, correct to one decimal place, the standard deviation of the numbers: -1, 5, 0, 2 and 9.
-
A.
7.2 -
B.
6.6 -
C.
3.6 -
D.
3.2
Correct Answer: Option C
Explanation
| (x) | -1 | 5 | 0 | 2 | 9 | Total = 15 |
| (x – bar {x}) | -4 | 2 | -3 | -1 | 6 | |
| ((x – bar{x})^{2}) | 16 | 4 | 9 | 1 | 36 | 66 |
Mean = (frac{15}{5} = 3)
SD = (sqrt{frac{sum (x – bar {x})^{2}}{n}})
= (sqrt{frac{66}{5}} )
= (sqrt{13.2})
= 3.6