Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Number systemEasy · 45s
What is the sum of the first 10 natural numbers?
TopicNumber system
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.
Solve step-by-step using number system concepts. What is the sum of the first 10 natural numbers? → 55
Final Answer: Option B — 55