What is the greatest common multiple of 12 and 20, and what is the least common multiple of 16, 12 and 20

What is the greatest common multiple of 12 and 20, and what is the least common multiple of 16, 12 and 20

What is the greatest common multiple of 12 and 20? There is no greatest common multiple
12=2*2*3
20=2*2*5
The greatest common factor of 12 and 20 is 2 * 2 = 4
The least common multiple is 2 * 2 * 3 * 5 = 60
What is the least common multiple of 16, 12 and 20
16==2*2*2*2
12=2*2*3
20=2*2*5
The greatest common factor of 16, 12 and 20 is 2 * 2 = 4
The least common multiple is 2 * 2 * 2 * 2 * 3 * 5 = 240

The greatest common multiple of 12 and 20 is () and the least common multiple of 16, 12 and 20 is (). The least common multiple is ()

(12,20)=4
[12,20]=60

What is the least common multiple of 12 and 16______ ．

12 = 2 × 2 × 3, 16 = 2 × 2 × 2 × 2, the least common multiple of 12 and 16 is: 2 × 2 × 2 × 3 = 48, so the answer is: 48