Respuesta :
The LCM of two prime numbers is generally just their product, since they share no common factors.
3 and 7 are both prime numbers, so their LCM (least common multiple) is simply the numbers multiplied together. In this case, the LCM is thus 21.
Answer: 21
Step-by-step explanation: To find the least common multiple or lcm of 3 and 7, begin by finding the first few multiples of each number and comparing the lists.
Multiples of 3
1 × 3 = 3
2 × 3 = 6
3 × 3 = 9
4 × 3 = 12
5 × 3 = 15
6 × 3 = 18
7 × 3 = 21
Multiples of 7
1 × 7 = 7
2 × 7 = 14
3 × 7 = 21
Since 21 appears in both lists, we can stop here.
Therefore, the least common multiple of 3 and 7 is 21.