JAMB - Mathematics (1993 - No. 38)
Calculate the standard deviation of the following data: 7, 8, 9, 10, 11, 12, 13.
2
4
10
11
설명
\(\begin{array}{c|c} x & x - x & (x - x)^2\\ \hline 7 & -3 & 9\\8 & -2 & 4 \\9 & -1 & 1\\10 & 0 & 1\\11 & 1 & 1\\ 12 & 2 & 4\\13 & 3 & 9\\ \hline & & 28\end{array}\)
S.D = \(\sqrt{\frac{\sum(x - x)^2}{N}}\)
= \(\sqrt{\frac{\sum d^2}{N}}\)
= \(\sqrt{\frac{28}{7}}\)
= \(\sqrt{4}\)
= 2
S.D = \(\sqrt{\frac{\sum(x - x)^2}{N}}\)
= \(\sqrt{\frac{\sum d^2}{N}}\)
= \(\sqrt{\frac{28}{7}}\)
= \(\sqrt{4}\)
= 2