Question

1.What's the least common multiple of 9,12,15.

2.Whats the least common multiple of 4,7,10

3.Whats the common multiple of 6,7,9

Answer 1

1. 180 
2. 140
3.126 (you meant least common multiple right?)

Answer 2

Its 180 
140 
and 126

Hope this helps :D