Given that the mean of the scores 15, 21, 17, 26, 18 and 29 is 21, calculate the standard deviation of the scores
- \(\sqrt{10}\)
- 4
-
5
- \(\sqrt{30}\)
The correct answer is: C
Explanation
\(\begin{array}{c|c} x & x - x & (x - \bar{x})^2\\ \hline 15 & -6 & 36\\21 & 0 & 0\\17 & -4 & 16\\ 26 & 5 & 25 \\ 18 & -3 &9 \\ 29 & 8 & 64 \end{array}\)\(E(x - \bar{x})^2\) = 150
N = 6
S.D = \(\sqrt{\frac{(x - x)^2}{N}}\)
S.D = \(\sqrt{\frac{150}{6}}\) = 5