Least Common Multiple of 28 and 42?

Answer 1

28 can be factored into 2, 2, and 7.

42 can be factored into 2, 3, and 7.

The most number of times two occurs in a single prime factorization is twice; three occurs once, and seven occurs once, so we do:

2 × 2 × 3 × 7 = 84.