Answer:
1,260
Step-by-step explanation:
The least common multiple is the product of all factors in the greatest number of their occurrence.
LCM = 2*2*3*3*5*7
LCM = 2²*3²*5*7
LCM = 1260
The least common multiple of 30, 36 and 42 is 1260.
-hope it helps
