Solved UPSC CDS/OTA Question
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Q · Statistics Moderate · 45s
Find the mean for grouped data with classes 0–10,10–20,20–30,30–40 and frequencies 5,9,7,4 (use class midpoints).
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.
x̄ = Σf·mid / Σf = 19.00.
Final Answer: Option B — 19.00