Question

The frequency distribution given below shows the weight of 40 students of a class. Find the median weight of the students.

Weight (in kg):	40-45	45-50	50-55	55-60	60-65	65-70
No. of Students:	9	5	8	9	6	3

Answer 1

The cumulative frequencies are `9,\ 14,\ 22,\ 31,\ 37,\ 40` and `N/2=20`. 

The median class is `50\text{–}55` kg.

Here, `l=50,\ F=14,\ f=8,\ h=5`.

\[\text{Median}=50+\left(\frac{20-14}{8}\right)\times5\]

Therefore: \[\text{Median weight}=53.75\text{ kg}\]