text: It is the smallest (non-zero) number that is a multiple of the denominators. For instance, the LCD of {1/2, 1/4} is 4 because the least common multiple of 2 and 4 is 4. Likewise the LCD of {1/2, 1/3} is 6.\n\nBy using this (or any multiple of it) as a denominator, it enables addition, subtraction or comparison of fractions:\n\n1/2 + 1/4 = 2/4 + 1/4 = 3/4; \n1/2 − 1/3 = 3/6 − 2/6 = 1/6; \n1/3 < 2/5 since 5/15 < 6/15.