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NTA Abhyas JEE Main2020MathematicsStatisticsPractice

The arithmetic mean of a set of 50 numbers is 38 . If two numbers of the set, namely 60 and 40 are discarded, the arithmetic mean of the remaining set of numbers is

Options

  1. A38.5
  2. B37.5
  3. C36.5
  4. D36

Correct answer

B. 37.5

Step-by-step solution

Given Σ x i 50 = 38 , Σ x i = 1900 New value of Σ x i = 1900 - 60 - 40 = 1800 , n = 48 New mean = 1800 48 = 37.5

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