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NTA Abhyas JEE Main2020MathematicsStatisticsPractice

The mean of a data set comprising of 16 observations is 16 . If one of the observation valued 16 is deleted and three new observations valued 3, 4 and 5 are added to the data, then the mean of the resultant data is

Options

  1. A14.0
  2. B16.8
  3. C16.0
  4. D15.8

Correct answer

A. 14.0

Step-by-step solution

Given, ( ∑ i = 1 15 x i ) + 16 16 = 16 ⇒ ∑ i = 1 15 x i +16 = 256 ∑ i = 1 15 x i = 240 Required mean = ∑ i = 1 15 x i + 3 + 4 + 5 18 = 240 + 3 + 4 + 5 18 = 252 18 = 14

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