HCF and LCM

HCF and LCM

Core facts:

For two numbers: HCF * LCM = product of numbers
HCF = product of common prime factors with minimum powers
LCM = product of all prime factors with maximum powers

For fractions:

HCF of fractions = HCF(numerators) / LCM(denominators)
LCM of fractions = LCM(numerators) / HCF(denominators)

Euclid algorithm:

HCF(a,b) = HCF(b, remainder when a is divided by b)