Let us find the m

To find out median, we need to calculate cumulative frequency for the given data.

Let us make a table for that.

Here, n = 80, that is, n = even.

Since, n is even, median can be found out as:

⇒

⇒ Median = The mean of 40^th and 41^th observations

And we know that, 40^th observation = 22 [∵ 40 comes between 33 and 57]

And 41^th observation = 22 [∵ 41 comes between 33 and 57]

Median = Mean of 22 and 22

⇒

⇒

⇒ Median = 22

Thus, median = 22.