JEE Mains · Maths · STD 11 - 13. statistics
The mean and standard deviation of \(50\) observations are \(15\) and \(2\) respectively. It was found that one incorrect observation was taken such that the sum of correct and incorrect observations is \(70\) . If the correct mean is \(16\) , then the correct variance is equal to
- A \(10\)
- B \(36\)
- C \(43\)
- D \(60\)
Answer & Solution
Correct Answer
(C) \(43\)
Step-by-step Solution
Detailed explanation
No. of observations: - \(50\) mean \((\bar{x})=15\) Standard deviation \((\sigma)=2\) Let incorrect observation is \(x_{1}\) and correct observation is \(\left( x _{1}^{\prime}\right)\) Given \(x_{1}+x_{1}^{\prime}=70\)…
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