JEE Mains · Maths · STD 11 - 13. statistics
The outcome of each of \(30\) items was observed; \(10\) items gave an outcome \(\frac{1}{2} - d\) each, \(10\) items gave outcome \(\frac {1}{2}\) each and the remaining \(10\) items gave outcome \(\frac{1}{2} + d\) each. If the variance of this outcome data is \(\frac {4}{3}\) then \(\left| d \right|\) equals
- A \(\frac {2}{3}\)
- B \(2\)
- C \(\frac {\sqrt 5}{2}\)
- D \(\sqrt 2\)
Answer & Solution
Correct Answer
(D) \(\sqrt 2\)
Step-by-step Solution
Detailed explanation
Variance remains some if same number is subracted from each observation. (subtract \(10\) from each observation)…
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