Finding Lowest or Least Common Denominator (LCD) 
of Fractions

Finding Lowest Common Denominator (LCD)

The lowest common denominator or least common denominator (abbreviated LCD) is the least common multiple of a set of fractions. It is the smallest number that both denominators can divide by evenly.


Example: The LCD of the fraction below is 36


36 least common multiples of 12 and 18 because 36 is the smallest number that both 12 and 18 can divide by evenly (with no remainder.

finding fractions lcd

These two fractions can know be added or subtracted