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In a set of 2 n distinct observations, each of the observation 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 :

Options

  1. AIncreases by 2 .
  2. BIncreases by 1 .
  3. CDecreases by 2 .
  4. DDecreases by 1 .

Correct answer

B. Increases by 1 .

Step-by-step solution

New mean = n Σ x i + 5n + n Σ y i - 3n 2n = n Σ x i + n Σ y i 2n + 2n 2n = old mean + 2n 2n = old mean + 1

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