Respuesta :

The least common multiple of 3 and 7 is 21

3,6,9,12,15,18,21
7,14,21
First, list multiples of 3 and 7. 3: 3, 6, 9, 12, 15, 18, 21... 7: 7, 14, 21... 21 is the LCM because it is the lowest multiple that the two share.