There is really no such thing as a "greatest common multiple". Once you find the least common multiple of a set of numbers, you can keep adding the LCM to itself over and over again. Each new number you get will be a common multiple of your set of numbers, but each new number will always be larger than the previous. This means that you can keep adding while the number approaches infinity and you will still never find a greatest multiple.
The Greatest Common Divisor (GCD) for 42 56 is 14.
GCD: 14 LCM: 280
14
56/1 = 56 56/2 = 28 56/4 = 14 56/7 = 8 1, 2, 4, 7, 8, 14, 28, 56
The GCF of 20, 28, and 56 is 4.
since 14 = 14 x 1 and 56 = 14 x 4 the answer is 14, since it divides evenly into both and clearly nothing larger will.There is a clever algorithm that can help you work this out in the general case:GCD(14, 56) = GCD(14, 56 - 14) = GCD(14, 42)This step (subtract the smaller from the larger) relies on the fact that any number that divides both 14 and 56 also divides 56 - 14.Repeat this:GCD(14, 42) = GCD(14, 42 - 14) = GCD(14, 28)GCD(14, 28) = GCD(14, 28 - 14) = GCD(14, 14)which is clearly 14.This is called Euclid's Algorithm.
The Greatest Common Divisor (GCD) for 56 84 is 28.
The Greatest Common Divisor (GCD) for 42 56 is 14.
GCD: 14
It is 28
7
GCF(56, 28, 14) = 14.
GCF(56, 28, 14) = 14.
gcf(14, 28, 56) = 14
GCD: 14 LCM: 280
Greatest Common Divisor (GCD) for 105 56 is 7.
It is 56:14, 28, 42, 56