Question

Find the mode of the following distribution.

Class-interval:	0 – 10	10 – 20	20 – 30	30 – 40	40 – 50	50 – 60	60 – 70	70 – 80
Frequency:	5	8	7	12	28	20	10	10

Answer 1

Class-interval:	0 – 10	10 – 20	20 – 30	30 – 40	40 – 50	50 – 60	60 – 70	70 – 80
Frequency:	5	8	7	12	28	20	10	10

l = 40, h = 50 – 40 = 10, f = 28, f₁ = 12 and f₂ = 20

Mode = `l + (f - f_2)/(2f - f_1 - f_2) xx h`

= `40 + (28 - 12)/(2 xx 28 - 12 - 20) xx 10`

= `40 + (16 xx 10)/24`

= `40 + 160/24`

= 40 + 6.67

= 46.67