Question

find the drithemtic mean of the data given below by step- deviation method.
classes. fi
0-10. 24
10-20. 31
20-30. 57
30-40. 28
40-50. 12​

Answer 1

Answer:

Class inreval

Mid values (x

i

)

Frequency (f

i

)

d

i

=x

i

−A

u

i

=

h

d

i

F

i

u

i

0-10

5

4

-20

-2

-8

10-20

15

6

-10

-1

-6

20-30

25=A

10

0

0

0

30-40

35

20

10

1

20

40-50

45

10

20

2

20

N=50

Total=26

h=10,A=25,N=50,∑f

i

u

i

=26

Mean (

x

)=A+h[

N

1

∑f

i

u

i

]

put the values

Mean=30.2