The combined mean of two groups is 50. If n₁=20, mean₁=45, and n₂=30, mean₂ is: MCQ with Answer and Explanation

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The combined mean of two groups is 50. If n₁=20, mean₁=45, and n₂=30, mean₂ is:

A. 50

B. 53.33

C. 55

D. 52

Answer: Option B

Solution (By JKSSB Mock Tests)

50 = (20×45 + 30×mean₂) / 50 → 2500 = 900 + 30×mean₂ → mean₂ = 1600/30 = 53.33.

This question belongs to: Accountancy and Statistics Statistics

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