Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · Number systemMedium · 45s
Find the product of HCF and LCM of 15 and 20.
TopicNumber system
Question Typemultiple choice
DifficultyMedium
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. Find the product of HCF and LCM of 15 and 20. → 300
Final Answer: Option B — 300