Question
Download Solution PDFLet \(\rm \Sigma_{i=1}^9x_i^2=885\) If M is the mean and σ is the standard deviation of x1, x2, x3.....x9 then what is the value of M2 + σ2?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFExplanation:
Given:
\(\rm \Sigma_{i=1}^9x_i^2=885\)
Variance σ = \(\rm \Sigma_{i=1}^9x_i^2 - (mean)^2\)
= \(\frac{855}{9} -(M)^2\)
\(x = {-b \pm \sqrt{b^2-4ac} \over 2a}\)
⇒ σ + M2 = \(\frac{855}{9} = 95\)
∴ Option (b) is correct.
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