Question

For the following distribution :

Class: 0-5 5-10 10-15 15-20 20-25

Frequency: 10 15 12 20 9

the sum of the lower limits of the median and modal class is
(a) 15 (b) 25 (c) 30 (d) 35

Answer 1

Class	Frequency	Cumulative Frequency
0–5	10	10
5–10	15	25
10–15	12	37
15–20	20	57
20–25	9	66

Here, N = 66.
$\therefore \frac{N}{2}=33$, which lies in the interval 10–15.
So, the lower limit of the median class is 10.
The highest frequency is 20, which lies in the interval 15–20.
Therefore, the lower limit of modal class is 15.
So, the required sum is 10 + 15 = 25.
Hence, the correct answer is option (b).