JEE Mains · Maths · STD 11 - 13. statistics
In a set of \(2n\) distinct observations, each of the observations below the median of all the observations is increased by \(5\) and each of the remaining observations is decreased by \(3\). Then the mean of the new set of observations
- A increases by \(1\)
- B decreases by \(1\)
- C decreases by \(2\)
- D increases by \(2\)
Answer & Solution
Correct Answer
(A) increases by \(1\)
Step-by-step Solution
Detailed explanation
There are \(2n\) abservations \({{x_1},{x_2},......,{x_{2n}}}\) So, maen \( = \sum\limits_{i = 1}^{2n} {\frac{{{x_i}}}{{2n}}} \) Let these observations be divided into two parts \({{x_1},{x_2},......,{x_n}}\) and \({x_{n + 1}},......{x_{2n}}\) Each in \({1^{st}}\) part \(5\) is…
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