Question

What is the LCD of 2/5 and 4/11

Answer 1

To find the lowest common denominator you need to know the factors of 5 and 11.
So make two lists:
5, 10, 15, 20, 25, 30, and so on.
11, 22, 33, 44, 55, 66, and so on.
Keep doing that until you find the lowest common number in the lists. The LCD will be 55.