Question

how to fond (xi - xbar ) in grouped data
how to calculate it ?​

Answer 1

We use the formula

xbar= a+ (summation fidi/N)* h

a= Assumed mean (choose any one from xi column)

di= xi-assumed mean/ class length

fidi= product of fi and di

N= number of observations (Summation of fi)

h= class length.

Answer 2

Finding ($x_i$ - X) by using $X = a+$∑$f_i d_i$×$\frac{h}{N}$.

Explanation:

First find X(bar)

$X = a+$∑$f_i d_i$×$\frac{h}{N}$

Where,

a = assumed mean

$f_id_i$ = product of $f_i$ and $d_i$

h = class length

N = number of observation

Now you can easily find out ($x_i$ - X).