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Question
In the formula `barx=a+h((sumf_iu_i)/(sumf_i))`, for finding the mean of grouped frequency distribution ui = ______.
Options
`(x_i+a)/h`
h(xi - a)
`(x_i-a)/h`
`(a-x_i)/h`
Solution
In the formula `barx=a+h((sumf_iu_i)/(sumf_i))`, for finding the mean of grouped frequency distribution ui = `(x_i-a)/h`.
Explanation:-
It is given that `barX = A +h (1/Nsumf_iu_i)`.
This is the formula to find mean of any data by step deviation method.
Here,
`u_i=(x_i-a)/h`
Where xi are the mid values, A is assumed mean and h is class size .
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