Question:
Find the mean, variance and standard deviation for the first six odd natural numbers
Solution:
Odd natural numbers = 1, 3, 5, 7, 9, …
First Six Odd Natural Numbers = 1, 3, 5, 7, 9, 11
To find: MEAN
We know that
$\operatorname{Mean}(\overline{\mathrm{x}})=\frac{\text { Sum of observations }}{\text { Total number of observations }}$
$=\frac{1+3+5+7+9+11}{6}$
$=\frac{36}{6}$
$\overline{\mathrm{x}}=6$
To find: VARIANCE
Variance, $\sigma^{2}=\frac{\sum\left(\mathrm{x}_{\mathrm{i}}-\overline{\mathrm{x}}\right)^{2}}{\mathrm{n}}$
$=\frac{70}{6}$
$=11.67$
To find: STANDARD DEVIATION
Standard Deviation $(\sigma)=\sqrt{\text { Variance }}$
$=\sqrt{11.67}$
$=3.41$