Question

Find the mean using the step deviation method.

Class	0-10	10-20	20-30	30-40	40-50
Frequency	6	10	15	9	10

Answer 1

Let a = 25 and h =10

Mean = a + (Σfu/Σf) × h

Mean = 25 + 10 × ( 7/50 ) = 26.4