Find the highest common factor (HCF) or greatest common divisor (GCD) of 84 and 126.
Note
Find prime factorizations: 84 = 2^2 × 3 × 7, 126 = 2 × 3^2 × 7. Take common primes with lowest powers: 2^1 × 3^1 × 7 = 42, so the GCD is 42.
Find the highest common factor (HCF) or greatest common divisor (GCD) of 84 and 126.
Find prime factorizations: 84 = 2^2 × 3 × 7, 126 = 2 × 3^2 × 7. Take common primes with lowest powers: 2^1 × 3^1 × 7 = 42, so the GCD is 42.