Question

calculate AM by direct assumed mean and step division method x= 1,2,3,4,5 frequency =5,10,15,10,5​

Answer 1

Explanation:

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

X =A+ ∑f∑fd ×i  

A= Assumed mean of the given data

∑ = Summation of the frequencies given in the grouped data

∑fd  

′

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

d  

′

=  

i

(x−A)

​  

 

i= Class interval width

X

 = arithmetic mean

X

=22.5+  

105

172

​  

×5

=22.5+8.19

=30.69 ≈ 31