The greatest common divisor of (1)6 and 2 1 is 3.
(2) The least common multiple of 6 and 2 1 is 42.
(3)96。
(4) Factors of 1 0:1,2,5, 10.
Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24.
Factors of 72: 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72.
(5) The first five multiples of 6: 6, 12, 18, 24, 30.
The first five multiples of 13: 13, 26, 39, 42, 65.
The first five multiples of 24: 24,48,72,96, 120.
(6) This question actually asks you to find the least common multiple of 13 and 18, so the minimum length of the square should also be 13x 18=234cm.
In fact, some of these questions should be in your book, so you should read the concepts and examples in the book. Of course, if you don't understand anything about the above questions, you can ask me ~