What is the HCF of 96 and 404?

1. Factorise both numbers into primes. 2. 96 = 2^5 x 3. 3. 404 = 2^2 x 101. 4. The common primes are only the 2s, and the lower power is 2^2. 5. So the HCF is 4. It cannot be 8 or 12, since 404 is not divisible by either. _Source: syllabus Maths, Ch 1 'Real Numbers', S1.2 The Fundamental Theorem of Arithmetic_