Solved UPSC CDS/OTA Question
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Q · Statistics Difficult · 45s
Two groups: (n, x̄, σ) = (20,50,6) and (30,56,8). Find the combined standard deviation.
TopicStatistics
Question Typemultiple choice
DifficultyDifficult
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained - no skipped algebra.
x̄_c=53.60; σ_c=√[ ... ] = 7.84.
Final Answer: Option D - 7.84