What is the greatest common factor of 10 and 11 What about 12 and 18? What about 15 and 25? What about 51 and 3? What about 3 and 7? What about 4 and 10?

What is the greatest common factor of 10 and 11 What about 12 and 18? What about 15 and 25? What about 51 and 3? What about 3 and 7? What about 4 and 10?

The greatest common factor of 10 and 11 is 1
The greatest common factor of 12 and 18 is 6
The greatest common factor of 15 and 25 is 5
The greatest common factor of 51 and 3 is 3
The least common multiple of 3 and 7 is 21
The least common multiple of 4 and 10 is 20