JEE Mains · Maths · STD 11 - 13. statistics
The mean and variance of \(7\) observations are \(8\) and \(16\) respectively. If two observations are \(6\) and \(8 ,\) then the variance of the remaining \(5\) observations is:
- A \(\frac{92}{5}\)
- B \(\frac{134}{5}\)
- C \(\frac{536}{25}\)
- D \(\frac{112}{5}\)
Answer & Solution
Correct Answer
(C) \(\frac{536}{25}\)
Step-by-step Solution
Detailed explanation
Let \(8,16, \mathrm{x}_{1}, \mathrm{x}_{2}, \mathrm{x}_{3}, \mathrm{x}_{4}, \mathrm{x}_{5}\) be the observations. Now \(\frac{x_{1}+x_{2}+\ldots+x_{5}+14}{7}=8....(i)\) \(\Rightarrow \sum_{i=1}^{5} x_{i}=42\) Also…
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