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A data set of n observations has mean 2 M , while another data set of 2 n observations has mean M . What is the mean of the combined data sets?

Options

  1. AM
  2. B3 M 2
  3. C2 M 3
  4. D4 M 3

Correct answer

D. 4 M 3

Step-by-step solution

Sum of n observation =2 M n Sum of 2 n observation =M 2 n Mean of combined data sets = 2 M n+2 M n (n+2 n) = 4 3 M .

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