Solved UPSC CDS/OTA Question
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Q · Statistics Difficult · 45s
Compute the Pearson correlation coefficient r for pairs (1,2),(2,4),(3,5),(4,4),(5,5).
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.
r=Σ[(x−x̄)(y−ȳ)] / √(Σ(x−x̄)² Σ(y−ȳ)²) = 0.775.
Final Answer: Option B — 0.775