Question

The following table shows the marks obtained by 50 students in mathematics of class 10 in a school.

Obtained marks	20-30	30-40	40-50	50-60	60-70	70-80
No. of students	5	9	8	12	13	3

Find the median marks.

Answer 1

n = 50 ⇒ n/2 = 25

But 25 comes under the cumulative frequency 34 and class interval against the cumulative frequency 34 is 50 – 60.

So, it is the median class.

∴ l = 50, cf = 22, f = 12 and h = 10

= 50 + 2.5 = 52.5

Hence, median marks = 52.5