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JEE Main20209 Jan 2020Morning ShiftMathematicsStatisticsActual

Let the observation x i 1 ≤ i ≤ 10 satisfy the equations ∑ i = 1 10 x i - 5 = 10 , ∑ i = 1 10 x i - 5 2 = 40 . If μ and λ are the mean and the variance of the observations, x 1 - 3 , x 2 - 3 , . . . . , x 10 - 3 , then the ordered pair μ , λ is equal to:

Options

  1. A3,3
  2. B6,3
  3. C6,6
  4. D3,6

Correct answer

A. 3,3

Step-by-step solution

Mean x i - 5 = ∑ x i - 5 10 = 1 ∴ M e a n x i - 5 + 2 = 3 μ = v a r x i - 5 = ∑ x i - 5 2 10 - ∑ x i - 5 10 = 3

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