Understanding the Greatest Common Divisor (GCD), which is also known as the Greatest Common Factor (GCF), is crucial when simplifying fractions. The GCD of two numbers is the largest number that can evenly divide both of them without leaving a remainder. For instance, to find the GCD of 27 and 81, list the factors of each number.
- Factors of 27: 1, 3, 9, 27
- Factors of 81: 1, 3, 9, 27, 81
Here, the greatest factor they both share is 27, which is the GCD.
When simplifying a fraction, finding the GCD is the first step because it leads to the most reduced form of a fraction. Dividing both the numerator and the denominator by the GCD ensures that the fraction is in its simplest form, which means you cannot simplify it any further using elementary arithmetic.