Question

If \[u_i = \frac{x_i - 25}{10}, \Sigma f_i u_i = 20, \Sigma f_i = 100, \text { then }\]`overlineX`

Options

• 23

• 24

• 27

• 25

Answer 1

Given: 

\[u_i = \frac{x_i - 25}{10}, \Sigma f_i u_i = 20 \text { and } \Sigma f_i = 100\]

Now,  `u_i = (x_i - A)/h`= \[\frac{x_i - 25}{10}\]

Therefore, h = 10 and A = 25

We know that

`overlineX = A+h{1/N sum f_iu_i}`

     `= 25 + 10{1/100 xx 20}`

    `=25 +10 xx 1/5`

    `=25 + 2`

`overlineX = 27`