Question

Ci 40-50 50-60 60-70 70-80 80-90 frequency 5 x 15 12 7 find mode if mode is 67

Answer 1

CI = [ 10-20] [ 20-30] [30-40] [ 40-50] [50-60]

F = [ 15 ] [ 30 ] [ 45 ] [ 12 ] [ 18 ]

Now,

Maximum class frequency is 45

Modal class = 30-40

Lower limit of madal class (Xk) = 30

Frequency of the modal class (Fk) = 45

Frequency of the class preceding the modal class (Fk-1) =30

Frequency of the class succeeding the modal class ( Fk+1) = 12

Class size (H) = 10.

Therefore,

Mode = Xk+(Fk-Fk-1)

********* ______ × H

***********2Fk - Fk-1 - Fk+1

=>. 30 + (45-30/90-30-12) × 10

=> 30 + 150/48

=> 30 + 75/24

=> 30 + 3.12

=> 33.12

HENCE,

MODE = 33.12

HOPE IT WILL HELP YOU.......

Answer 2

x=8

here f1=15 f0=x f2= 12

L=60. h=10

according to formula of mode

$l + (f1- fo \div 2f1 - fo - f2) \times h$

$67 = 60 + (15 - x \times 2 \times 15 - x - 12) \times 10$

by solving this we get

x= 8