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JEE Main201815 Apr 2018Morning ShiftMathematicsStatisticsActual

The mean of a set of 30 observations is 75 . If each other observation is multiplied by a nonzero number and then each of them is decreased by 25 , their mean remains the same. The is equal to equal to 0

Options

  1. A10 3
  2. B4 3
  3. C1 3
  4. D2 3

Correct answer

B. 4 3

Step-by-step solution

As mean is a linear operation, so if each observation is multiplied by and decreased by 25 then the mean becomes 75 -25 . According to the question, 75 -25=75 = 4 3

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