Question

Calculate the median from the following data:

Rent (in Rs.):	15 - 25	25 - 35	35 - 45	45 - 55	55 - 65	65 - 75	75 - 85	85 - 95
No. of Houses:	8	10	15	25	40	20	15	7

Answer 1

Class interval	Frequency	Cumulative frequency
15 - 25	8	8
25 - 35	10	18
35 - 45	15	33
45 - 55	25	58
55 - 65	40	98
65 - 75	20	118
75 - 85	15	133
85 - 95	7	140
	N = 140

Here N = 140

So, N/2 = 70

Thus, the cumulative frequency just greater than 70 is 98 and the corresponding class is 55 - 65.

Therefore, 55 - 65 is the median class.

Here, l = 55, f = 40, F = 58 and h = 10

We know that

Median `=l +{(N/2-F)/f}xxh`

`=55+{(70-58)/40}xx10`

`=55+(12xx10)/40`

`=55+120/40`

= 55 + 3

= 58

Hence, the median is 58.