12. The greatest common factor and the least common multiple of 16 and 30 24、16、18、 14、21、42、 22、77、42、 Say pull down, use short method, step by step, how to seek
First, 24.16.18 △ 2, = 12.8.9, after omitting 8, look at 12 and 9, then 8 is dragged down, which is 3, equal to 4.8.3. Then multiply them, the greatest common factor is 6, and the least common multiple is 576