Which procedure is used to reduce fractions?

The procedure used to reduce fractions involves identifying and cancelling common factors from the numerator and the denominator. When simplifying a fraction, the goal is to express it in its simplest form, where the numerator and denominator have no common factors other than 1. By recognizing common factors, you can divide both the numerator and the denominator by that factor, thus reducing the fraction.

For instance, if you have the fraction 8/12, you can identify that both numbers share a common factor of 4. By dividing both the numerator (8) and the denominator (12) by 4, the fraction simplifies to 2/3. This method effectively reduces the fraction to its simplest form, making it easier to work with in mathematical contexts.

The other methods mentioned, such as multiplying by the denominator, finding common denominators, or adding both the numerator and denominator, do not achieve the purpose of simplifying a fraction and are not utilized in the reduction process.