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2 Statistics

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Question 324

Group A contains 30 observations with mean 12 and variance 4. Group B contains 20 observations with mean 18 and variance 9.

a.

Calculate the mean of all 50 observations.

[2]
b.

Calculate the variance and standard deviation of all 50 observations.

[4]
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2 Statistics Questions

  1. A Level
  2. /Maths
  3. /2 Statistics

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