GCD & LCM
Section: Number PropertiesBank code: NUM-GCLGRE frequency: HighPro
1. Core Idea
- GCD (Greatest Common Divisor / HCF): the largest number that divides both. It is about splitting into equal groups.
- LCM (Least Common Multiple): the smallest number that both divide. It is about events lining up again.
The word-problem tell: "largest possible size / greatest number of identical pieces" -> GCD. "When will they next coincide / smallest quantity that works for both" -> LCM.
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