Answer:
420
Explanation:
We can find the prime factors of each of the numbers first before finding their LCM.
12: 2 × 2 × 3
30: 2 × 3 × 5
42: 2 × 3 × 7
To find the LCM, we need to see if they are any common prime factors between all three numbers. The common prime factors are 2 and 3. Then, we multiply 2 and 3 with the remaining outstanding factors, which are 2, 5, and 7.
LCM: 2 × 2 × 3 × 5 × 7 = 420