Solved UPSC CDS/OTA Question
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Q · Compound InterestPYQ · 45s
The difference between CI and SI on a sum for 2 years at 10% p.a. is ₹100. Find the principal.
TopicCompound Interest
Question Typemultiple choice
DifficultyPYQ
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
For 2 years: CI−SI = P·(r^2)/100^2 ⇒ 100 = P·(10^2)/10000 ⇒ P = ₹10,000.
Final Answer: Option A — ₹10000.00