Question

The marks obtained by $30$ students in a class assessment of $5$ marks is given below :

Marks	0	1	2	3	4	5
Number of Students	1	3	6	10	5	5

Calculate the mean, median and mode of the above distribution.

Answer 1

$x_f$		$fx$	$cf$
0	1	0	1
1	3	3	4
2	6	12	10
3	10	30	20
4	5	20	25
5	5	25	30
	$\sum f=30$	$\sum fx=90$

Mean $=\frac{\sum fx}{\sum f}=\frac{90}{30}$
$=3$
Median $=$ size of $\left(\frac{N}{2}\right)$th ${obs}^n$
$=$ size of $\left(\frac{30}{2}\right)$th ${obs}^n$
$=$ size of $15$th ${obs}^n$
$=3$
Mode $=3$ marks (as highest frequency is $10$.)