Find the least common multiple for each list of numbers 5, 7

Multiples of 5 are: 5,10,15,20,25,30,35,40,45, ...

Multiples of 7 are: 7,14,21,28,35,42,49,63, ...

So the least common number is these two sets is 35, which is the least common multiple of 5 and 7

Hope you got it