Solved UPSC CDS/OTA Question
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Q · Simple InterestModerate · 45s
The simple interest on a certain sum at 5% per annum for 9 months is ₹150. Find the principal.
TopicSimple Interest
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.
P = (SI×100)/(R×T) = (150×100)/(5×(9/12)) = ₹4000.
Final Answer: Option D — ₹4000.00