Solved UPSC CDS/OTA Question
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Q · LCM and HCFModerate · 45s
The HCF of two numbers is 18, and their LCM is 180. If one number is 90, find the other number.
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.
Product = HCF × LCM = 18 × 180 = 3240; Other = 3240 ÷ 90 = 54.
Final Answer: Option D — 54