lcd


Definition of Least Common Denominator (LCD)

  • Least Common Denominator is the least common multiple of two or more of fractions.

More about Least Common Denominator (LCD)

  • It is also called as lowest common denominator.
  • Steps to find the Least Common Denominator:
  • 1. First find the multiples of the denominators.

    2. Identify the least common multiple.

Example of Least Common Denominator (LCD)

  • To find the least common denominator of the fractions and , first we need to find the multiples of the denominator 7 i.e. 7, 14, 21, 28, 35 . . . and the multiples of the denominator 3 i.e. 3, 6, 9, 12, 15, 18, 21, 24 . . . The least common multiple of the denominators 7 and 3 is 21.

So, the least common denominator of the fractionsand is 21.
Solved Example on Least Common Denominator (LCD)

Find the least common denominator of the given expression.
+
Choices:
A. 12
B. 16
C. 4
D. 21
Correct Answer: A
Solution:
Step 1: The denominators of the given fractions are 4 and 12.
Step 2: Multiples of 4 are 4, 8, 12, 16, 20 . . .
Step 3: Multiples of 12 are 12, 24, 36, 48 . . .
Step 4: The lowest multiple the numbers have in common is 12.
Step 5: So, the least common denominator of the given fractions is 12.

Related Terms for Least Common Denominator (LCD)

  • Common multiple
  • Denominator
  • Greatest Common Factor
  • Least Common Multiple (LCM)
  • Multiple