JEE Mains · Maths · STD 11 - 13. statistics
Consider the statistics of two sets of observations as follows :
| Size | Mean | Variance | |
| Observation \(I\) | \(10\) | \(2\) | \(2\) |
| Observation \(II\) | \(n\) | \(3\) | \(1\) |
- A \(8\)
- B \(10\)
- C \(5\)
- D \(15\)
Answer & Solution
Correct Answer
(C) \(5\)
Step-by-step Solution
Detailed explanation
\(\sigma^{2}=\frac{ n _{1} \sigma_{1}^{2}+ n _{2} \sigma_{2}^{2}}{ n _{1}+ n _{2}}+\frac{ n _{1} n _{2}}{\left( n _{1}+ n _{2}\right)}\left(\overline{ x }_{1}-\overline{ x }_{2}\right)^{2}\) \(n _{1}=10, n _{2}= n , \sigma_{1}^{2}=2, \sigma_{2}^{2}=1\)…
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