Answer:
1680
Step-by-step explanation:
First do the prime factorization:
16=2x2x2x2
28=2x2x7
42=2x3x7
60=2x2x3x5
To find least common multiple (LCM), write down all prime factors of one of the number and multiply by factors from other numbers that was not in that number:
LCM=2x2x3x5x7x2x2=1680
