Least common denominator calculator

LCD(1/2, 2/3, 5/4) = LCM(2, 3, 4) = 22×3 = 12

1/2 = 6/12

2/3 = 8/12

5/4 = 15/12

For example, to continue with the fraction calculator, calculate the sum of fractions 1/2 + 2/3 + 5/4.

What is LCD?

The lowest common denominator or least common denominator (abbreviated LCD) is the least common multiple of the denominators of a set of fractions. LCD is the smallest positive integer that has multiple denominators in the set. Fractions write with fraction bar / like 3/4.

Example: for LCD calculation of three fractions 1/2 2/3 5/4, enter 1/2 2/3 5/4.

How to calculate LCD

The same fraction we can express in many different forms. If the ratio between the numerator and denominator is the same, the fractions represent the same rational number.

The least common denominator of a set of fractions is the least number that is a multiple of all the denominators: their "least common multiple".
The method of calculating the LCD is the same as the calculation least common multiple of fractions denominators.
The simple method for common computing denominators (not least at all) is to multiply all denominators.

Questions and word problems to LCD

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