Question

ci=0-5,5-10,10-15,15-20,20-25,25-30
frequency=4,5,63,2,9
CF=a,d,b,c,e,f
find a,b,c,d,e and f
​

Answer 1

Answer:

X Mid point (x) Frequency (F) i=class interval width A=22.5 Assumed mean u=

i

x−A

fu

0-5 2.5 3 5 22.5 -4 -12

5-10 7.5 5 5 22.5 -3 -15

10 -15 12.5 7 5 22.5 -2 -14

15-20 17.5 8 5 22.5 -1 -8

20-25 22.5=A 10 5 22.5 0 0

25-30 27.5 11 5 22.5 1 11

30-35 32.5 14 5 22.5 2 28

35-40 37.5 19 5 22.

5 3 57

40-45 42.5 15 5 22.5 4 60

45-50 47.5 13 5 22.5 5 65

Σf=105 Σfu=172

The formula used for arithmetic mean of grouped data by step deviation method is,

X

=A+

∑f

∑fu

×i

A= Assumed mean of the given data

∑ = Summation of the frequencies given in the grouped data

∑fu = Summation of the frequencies and deviation of a given mean data

u=

i

(x−A)

i= Class interval width

X

= arithmetic mean

X

=22.5+

105

172

×5

=22.5+8.19

=30.69 ≈ 31

I think this is your answer

Mark as brainlist please follow me