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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
Solution
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`
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