Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Statistics Moderate · 45s
For data 10,12,15,18,21,24,27,30,33 find Q₁ (Tukey method).
TopicStatistics
Question Typemultiple choice
DifficultyModerate
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Lower half: 10,12,15,18 ⇒ Q₁ = (12+15)/2 = 13.5.
Final Answer: Option C — 13.5