Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Simple InterestEasy · 45s
Find the principal if the simple interest for 4 years at 8% per annum is ₹640.
TopicSimple Interest
Question Typemultiple choice
DifficultyEasy
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) = (640×100)/(8×4) = ₹2000.
Final Answer: Option C — ₹2000.00