Question

Calculate the median for the following data

Class interval	$1-5$	$6-10$	$11-15$	$16-20$	$21-25$	$26-30$	$31-35$
Frequency	$1$	$18$	$25$	$26$	$7$	$2$	$1$

Answer 1

Class	Frequency ($f_i$)	Cumulative Frequency
0.5-5.5	1	1
5.5-10.5	18	19
10.5-15.5	25	44
15.5-20.5	26	70
20.5-25.5	7	77
25.5-30.5	2	79
30.5-35.5	1	80=n

$\frac{n}{2}=40$

$l=10.5;h=5;f=25;c=19$

median$=l+\frac{h}{f}\times (\frac{n}{2}-c)$

$=10.5+\frac{5}{25}\times (40-19)=10.5+\frac{11}{5}=12.7$