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The mean of a data set comprising of 16 observations is 16 . If one of the observation value 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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