Multiples of 3 less than 20 are {3,6,9,12,15,18}.
5
21 24 27 30 33
3,6,9,12,15,18
834667
39
30
30
30
20
1, 2, 3, 4
The multiples of 4 with products equal or less than 20 are: 1 x 4 = 4 2 x 4 = 8 3 x 4 = 12 4 x 4 = 16 5 x 4 = 20
3,6,9,12,15,18,21,24,27
81, 84, 87.
15, 30 and 45
1, 2, 3, 4
Three of them.
6, 12, 18
The multiples of 4 with products equal or less than 20 are: 1 x 4 = 4 2 x 4 = 8 3 x 4 = 12 4 x 4 = 16 5 x 4 = 20
4 numbers less than 70 that are multiples of 3 and 5
3. All other multiples of 3 are not prime.
33
Here are all 13 of them: 15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165, 180, 195
3,6,9,12,15,18,21,24,27
81,84,87,90
There are 3 such numbers: 30, 60, 90.
3, 9, and 15. 6 and 18 are also multiples of 3, but are even.