Classifying the observations $0, 3, 2, 5, 7, 8, 10, 12, 5, 6, 6, 4, 14, 18, 20$ of a data,the frequency of class $0-5$ is ........

The marks obtained (out of $50$ marks) by $30$ students in a mathematics test are as given below:
$37, 22, 35, 42, 10, 16, 31, 22, 20, 27$
$27, 20, 31, 40, 35, 40, 27, 16, 47, 22$
$40, 22, 35, 20, 37, 20, 37, 47, 42, 31$
Represent this data in a frequency distribution table.

Find the mode of the following observations: $14, 25, 28, 29, 17, 14, 19, 22, 14, 30, 16, 28, 14, 25$.

The following observations are arranged in ascending order:
$26, 29, 42, 53, x, x+2, 70, 75, 82, 93$
If the median is $65,$ find the value of $x$.

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 following are the marks (out of $100$) of $60$ students in mathematics:
$16, 13, 5, 80, 86, 7, 51, 48, 24, 56, 70, 19, 61, 17, 16, 36, 34, 42, 34, 35, 72, 55, 75, 31, 52, 28, 72, 97, 74, 45, 62, 68, 86, 35, 85, 36, 81, 75, 55, 26, 95, 31, 7, 78, 92, 62, 52, 56, 15, 63, 25, 36, 54, 44, 47, 27, 72, 17, 4, 30$
Construct a grouped frequency distribution table with a class width of $10$,such that one of the classes is $10-20$ ($20$ not included).