Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Statistics Moderate · 45s
Given a discrete distribution X with values 0,1,2,3 having probabilities 0.1,0.3,0.4,0.2, find E[X].
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.
E[X]=Σx·p = 1.70.
Final Answer: Option B — 1.70