The greatest common divisor (gcd) = 3. This is probably what you mean. Otherwise, the lowest common multiple (lcm) = 168.
The only commom factor of 21 and 24 (apart from 1 which is a common factor of any set of numbers) is 3.
The highest common factor of 21 and 24 is 3.
the greatest common factor for 21 and 24 is 3.
The Greatest Common Factor of 21, 24, 14: 1
The greatest factor common to both 21 and 24 is 3.
The greatest commonfactor(gcf) of 24 and 21 is 3
The highest common factor is 3.
The GCF of 21, 24, and 36 is 3.
3
The Greatest Common Factor (GCF) is: 3
The GCF is 3.
The answer is simply three.