


Prime Factors, HCF and LCMHighest Common Factor (HCF)We say that d is a common factor of a and b if d is a factor of both a and b. We say that d is the highest common factor of a and b if there is no other factor of both a and b that is greater than d. Notation: HCF(a,b) = “highest common factor of a and b” . This is also sometimes denoted by GCD(a,b) read as “the greatest common divisor of a and b”.
To find the HCF of two numbers:
ExampleClick the question marks to see the example step by step. ExerciseFind the highest common factor (HCF) of each pair of numbers. << Prime Factorisation  HCF and LCM Index  Lowest Common Multiple (LCM) >>
