Question

For the following distribution:
Below: 10 20 30 40 50 60

Number of students: 3 12 27 57 75 80

the modal class is

(a) 10-20 (b) 20-30 (c) 30-40 (d) 50-60

Answer 1

Below	Class Interval	Cumulative Frequency	Frequency
10	0–10	3	3
20	10–20	12	9
30	20–30	27	15
40	30–40	57	30
50	40–50	75	18
60	50–60	80	5

Here, N = 80.
$\therefore \frac{N}{2}=40$, which lies in the interval 30–40.
Therefore, the modal class is 30–40.
Hence, the correct answer is option (c).