Mathematics for IGCSE & O level - Number (Section 3 - No. 33)

What is the highest common factor (HCF) of 48 and 84?

The prime factorization of 48 is 2 x 2 x 2 x 2 x 3, while that of 84 is 2 x 2 x 3 x 7. The HCF is 2 x 2 x 3 = 12.