Solved UPSC CDS/OTA Question
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Q · LCM and HCFDifficult · 45s
Find the least number which when divided by 12, 18, 21, and 30 leaves the remainder 10 in each case.
TopicLCM and HCF
Question Typemultiple choice
DifficultyDifficult
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
LCM(12,18,21,30) = 1260; Required = 1260 + 10 = 1270.
Final Answer: Option C — 1270