Solved UPSC CDS/OTA Question
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Q · Simple InterestModerate · 45s
A sum doubles itself in 12 years at simple interest. Find the rate of interest per annum.
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.
If the amount doubles, SI = P in 12 years ⇒ R = 100/12 = 8.33%.
Final Answer: Option A — 8.33%