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NTA Abhyas JEE Main2020MathematicsStatisticsPractice

If the mean of a set of observations x 1 , x 2 , . . . . . , x 10 is 40 , then the mean of x 1 + 4 , x 2 + 8 , x 3 + 12 , . . . . , x 10 + 40 is

Options

  1. A54
  2. B62
  3. C38
  4. D50

Correct answer

B. 62

Step-by-step solution

M e a n = x 1 + 4 + x 2 + 8 + x 3 + 12 + . . . + x 10 + 40 10 = x 1 + x 2 + . . . + x 10 10 + 4 1 + 2 + 3 + . . . + 10 10 = 40 + 22 = 6 2

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