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AP EAMCET2020MathematicsStatistics

If the mean of two samples of sizes 20 and 30 are 25 and 10 respectively, their variances are 9 and 16 respectively, their combined variance is

Options

  1. A67.9
  2. B68.2
  3. C68.1
  4. D67.2

Correct answer

D. 67.2

Step-by-step solution

No solution. Refer to answer key.

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