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Class 10 · Mathematics (Basic) · Unit 1: Real Numbers

HCF and LCM by Prime Factorisation

Lesson 2 of 5
Write each number as a product of primes. Then HCF=\text{HCF} = product of smallest powers of common primes; LCM=\text{LCM} = product of greatest powers of all primes involved. For two positive integers a,ba,b: HCF(a,b)×LCM(a,b)=a×b\text{HCF}(a,b) \times \text{LCM}(a,b) = a\times b.
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v1.1 · Sept 2026