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JEE Mains · Maths · STD 11 - 13. statistics
Mean of \(5\) observations is \(7.\) If four of these observations are \(6, 7, 8, 10\) and one is missing then the variance of all the five observations is
- A \(4\)
- B \(6\)
- C \(8\)
- D \(2\)
Answer & Solution
Correct Answer
(D) \(2\)
Step-by-step Solution
Detailed explanation
Let \({5^{th}}\) observation be \(x\). Given mean \(=7\) \(\therefore 7 = \frac{{6 + 7 + 8 + 10 + x}}{5}\) \( \Rightarrow x = 4\) Now, Variance…
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