Solved UPSC CDS/OTA Question
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Q · Statistics Difficult · 45s
Find the 90th percentile (P₉₀) for grouped data with classes 0–20,20–40,40–60,60–80 and frequencies 8,12,15,5.
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.
N=40, c=0.9N, percentile class 60–80; P₉₀ = 64.00.
Final Answer: Option A — 64.00