First 10 natural numbers are 1,2,3,4,5,6,7,8,9,10
So, N =10
| Xi |
X2i |
| 1 |
1 |
| 2 |
4 |
| 3 |
9 |
| 4 |
16 |
| 5 |
25 |
| 6 |
36 |
| 7 |
49 |
| 8 |
64 |
| 9 |
81 |
| 10 |
100 |
| Σxi = 55 |
Σx2i = 385 |
Variance = \(\Big(\frac{\Sigma x^2_i}{N} - \Big(\frac{\Sigma x_i}{N}\Big)^2\Big)\)
\(\sigma =\sqrt{\Big(\frac{385}{10} - \Big(\frac{55}{10}\Big)^2\Big)}\)
\(\sigma = \sqrt{38.5-30.25}\)
\(\sigma = \sqrt{8.25}\)
Hence, SD is 2.87
