What is the median of the following distribution? \[ \begin{array}{|c|c|} \hline x_i & f_i \\ \hline 8 & 4 \\ 9 & 6 \\ 10 & 2 \\ 11 & 3 \\ 12 & 7 \\ 13 & 6 \\ 14 & 4 \\ \hline \end{array} \]
Let the Mean and Variance of five observations $ x_i $, $ i = 1, 2, 3, 4, 5 $ be 5 and 10 respectively. If three observations are $ x_1 = 1, x_2 = 3, x_3 = a $ and $ x_4 = 7, x_5 = b $ with $ a>b $, then the Variance of the observations $ n + x_n $ for $ n = 1, 2, 3, 4, 5 $ is
Find the variance of the following frequency distribution:
| Class Interval | ||||
| 0--4 | 4--8 | 8--12 | 12--16 | |
| Frequency | 1 | 2 | 2 | 1 |
