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JEE Mains · Maths · STD 11 - 13. statistics
The sum of \(100\) observations and the sum of their squares are \(400\) and \(2475\), respectively. Later on, three observations, \(3, 4\) and \(5\), were found to be incorrect . If the incorrect observations are omitted, then the variance of the remaining observations is
- A \(8.25\)
- B \(8.50\)
- C \(8\)
- D \(9\)
Answer & Solution
Correct Answer
(D) \(9\)
Step-by-step Solution
Detailed explanation
\(\sum\limits_{i = 1}^{100} {{x_i}} = 400\) \(\sum\limits_{i = 1}^{100} {x_i^2} = 2475\) Variance \({\sigma ^2} = \frac{{\sum {x_i^2} }}{N} - {\left( {\frac{{\sum {{x_i}} }}{N}} \right)^2}\) \( = \frac{{2475}}{{97}} - {\left( {\frac{{388}}{{97}}} \right)^2}\)…
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