WAEC - Further Mathematics (2011 - No. 27)
Find the standard deviation of the numbers 3,6,2,1,7 and 5.
2.00
2.16
2.50
2.56
คำอธิบาย
| \(x\) | 3 | 6 | 2 | 1 | 7 | 5 | Total = 24 |
| \(x - \bar{x}\) | -1 | 2 | -2 | -3 | 3 | 1 | |
| \((x - \bar{x})^{2}\) | 1 | 4 | 4 | 9 | 9 | 1 | 28 |
\(\bar{x} = \frac{24}{6} = 4\)
\(S.D = \sqrt{\frac{\sum (x - \bar{x})^{2}}{n}}\)
= \(\sqrt{\frac{28}{6}} = \sqrt{4.667} = 2.16\)