Question

The age of teachers of a school are recorded below.

Age (in years)	20 - 30	30 - 40	40 - 50	50 - 60	60 - 70
No. of teachers	6	8	12	10	5

Draw a frequency polygon on the graph.

Answer 1

Class	20 - 30	30 - 40	40 - 50	50 - 60	60 - 70
Mid-value	25	35	45	55	65
Frequency	6	8	12	10	5