Solved UPSC CDS/OTA Question
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Q · LCM and HCFEasy · 45s
Three bells ring at intervals of 12, 15, and 20 minutes. If they ring together at 9:00 AM, when are they next together?
TopicLCM and HCF
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.
LCM = 60 min ⇒ 10:00 AM.
Final Answer: Option C — 10:00 AM