JEE Mains · Maths · STD 11 - 13. statistics
The mean and the variance of five observations are \(4\) and \(5.20,\) respectively. If three of the observations are \(3, 4\) and \(4;\) then the absolute value of the difference of the other two observations, is
- A \(7\)
- B \(5\)
- C \(1\)
- D \(3\)
Answer & Solution
Correct Answer
(A) \(7\)
Step-by-step Solution
Detailed explanation
Mean \(\bar x = 4,{\sigma ^2} = 5.2,n = 5,{x_1} = 3,{x_2} = 4 = {x_3}\) \(\sum {{x_i} = 20} \) \({x_4} + {x_5} = 9\,\,\,\,\,\,\,........\left( i \right)\) \(\frac{{\sum {x_i^2} }}{x} - {\left( {\bar x} \right)^2} = {\sigma ^2} \Rightarrow \sum {x_i^2} = 106\)…
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