It is very easy to find the Least Common Multiple. L.C.M is defined as the smallest whole number that is divisible by each number in a set of numbers. Here is the process of finding L.C.M.
First of all find the multiples of each number i.e
Multiples of 70: 70, 140, 190....
Multiples of 6 :12,18,24,30, 36, 42,48,54,60,66,72...
Thus, the least common multiple of 70 and 6 is 140.
