JEE Mains · Maths · STD 11 - 13. statistics
If the standard deviation of the numbers \(-1, 0, 1, k\) is \(\sqrt 5\) where \(k > 0,\) then \(k\) is equal to
- A \(4\sqrt {\frac {5}{3}}\)
- B \(\sqrt 6\)
- C \(2\sqrt 6\)
- D \(2\sqrt {\frac {10}{3}}\)
Answer & Solution
Correct Answer
(C) \(2\sqrt 6\)
Step-by-step Solution
Detailed explanation
\(S.D. = \sqrt {\frac{{\sum {{{\left( {x - \bar x} \right)}^2}} }}{n}} \) \(\bar x = \frac{{\sum x }}{4} = \frac{{ - 1 + 0 + 1 + k}}{4} = \frac{k}{4}\) Now…
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