Median of the following numbers: $4, 4, 5, 7, 6, 7, 7, 12, 3$ is

The marks obtained (out of $25$ marks) by $40$ students in an examination are as given below:
$\begin{array}{rrrrrrrrrr} 8, & 12, & 23, & 9, & 5, & 20, & 16, & 3, & 6, & 23 \\ 10, & 6, & 21, & 1, & 18, & 17, & 18, & 16, & 16, & 12, \\ 3, & 15, & 21, & 7, & 12, & 5, & 2, & 7, & 13, & 24, \\ 13, & 18, & 8, & 2, & 20, & 5, & 13, & 7, & 23, & 16 \end{array}$
Represent the data given above by a grouped frequency distribution table,taking the class intervals as $0-5, 5-10, \dots$ etc.

The information regarding the marks scored by $30$ students in a $50$ marks test is given below:

Marks $(x_{i})$	$15$	$22$	$28$	$31$	$35$	$40$	$44$	$46$
Number of students $(f_{i})$	$2$	$3$	$5$	$6$	$6$	$4$	$3$	$1$

Find the mean of the data.

Find the mean of the first seven natural numbers.

If $\bar{x}$ is the mean of $x_{1}, x_{2}, \ldots, x_{n}$ and $\bar{y}$ is the mean of $y_{1}, y_{2}, \ldots, y_{n}$. If $\bar{z}$ is the mean of $x_{1}, x_{2}, \ldots, x_{n}, y_{1}, y_{2}, \ldots, y_{n}$,then $\bar{z}$ is equal to

The points scored by a basketball team in a series of matches are as follows:
$17, 2, 7, 27, 25, 5, 14, 18, 10, 24, 48, 10, 8, 7, 10, 28$
Find the median and mode for the data.