Least Common Denominator Calculator
Find the least common denominator for two to six fractions, reduce inputs first, and show equivalent fractions with the LCD.
Examples:
Find the LCD for fractions
English users usually ask for the least common denominator calculator or LCD calculator. The expected method is to reduce fractions when needed, take the least common multiple of the denominators, and rewrite each fraction with that denominator.
The least common denominator is the least common multiple of the denominators after reduction.
- Enter two to six fractions.
- The calculator reduces each fraction first.
- It finds the LCD and multiplies each numerator and denominator by the required factor.
Why the least common denominator matters
A common denominator is needed before adding, subtracting, or comparing many fractions. The least common denominator keeps the equivalent fractions smaller than using a simple product of denominators.
| Fractions | Reduced denominators | LCD |
|---|---|---|
| 2/4 and 1/6 | 2 and 6 | 6 |
| 3/4, 5/6, 7/12 | 4, 6, 12 | 12 |
| 2/9 and 5/6 | 9 and 6 | 18 |
Frequently Asked Questions
Sources and References
- LCD CalculatorLCM Calculator
- Least Common Denominator (LCD) CalculatorGraphCalc
- Lowest Common DenominatorWikipedia
- Least Common MultipleWolfram MathWorld
Calculations are based on the listed reference sources. Links open in a new tab.
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