Solved UPSC CDS/OTA Question
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Q · LCM and HCFModerate · 45s
Two numbers are in ratio 4:5 and their LCM is 180. Find HCF.
TopicLCM and HCF
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.
20×HCF=180 ⇒ HCF=9.
Final Answer: Option B — 9