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The mean of a data set consisting of 20 observations is 40 . If one observation 53 was wrongly recorded as 33 , then the correct mean will be:

Options

  1. A41
  2. B49
  3. C40.5
  4. D42.5

Correct answer

A. 41

Step-by-step solution

Correct mean = 20 40-33+55 20 =41.1 Nearest option : (a) 41

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