AP EAMCET · Maths · Statistics
Calculate variance if \(\Sigma x_i^2=18000\) and \(\Sigma x_i=960\), for 60 observations
- A 44
- B 22
- C 32
- D 6.63
Answer & Solution
Correct Answer
(A) 44
Step-by-step Solution
Detailed explanation
For 60 observations it's given that \(\Sigma x_i=960\) and \(\Sigma x_i^2=18000\) So, the variance \(=\frac{\Sigma x_i^2}{60}-\left(\frac{\Sigma x_i}{60}\right)^2=\frac{18000}{60}-\left(\frac{960}{60}\right)^2\) \[ =300-(16)^2=300-256=44 \]
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