Calculate the standard deviation of the following data: 7, 8, 9, 10, 11, 12, 13
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Correct Answer: Option A
Explanation:
S.D = \(\frac{\sqrt\sum (x - x)^2}{N} = \frac{\sum d^2}{N} = \frac{\sqrt{28}}{7}\)
= \(\sqrt{4}\)
= 2
| x | x - x | (x - x)\(^2\) |
| 7 | -3 | 9 |
| 8 | -2 | 4 |
| 9 | -1 | 1 |
| 10 | 0 | 1 |
| 11 | 1 | 0 |
| 12 | 2 | 4 |
| 13 | 3 | 9 |
| ------ | ||
| 28 |
S.D = \(\frac{\sqrt\sum (x - x)^2}{N} = \frac{\sum d^2}{N} = \frac{\sqrt{28}}{7}\)
= \(\sqrt{4}\)
= 2