What is the first step in adding fractions with unlike denominators?

The first step in adding fractions with unlike denominators is to find a common denominator. This is essential because fractions must refer to the same whole to be combined accurately. The common denominator is a number that each of the original denominators can divide into without leaving a remainder, allowing the fractions to be expressed in equivalent forms.

Once a common denominator is established, the fractions can be rewritten with that denominator. This may involve finding the least common multiple (LCM) of the denominators or choosing any other appropriate common denominator. After this step, adjusting the numerators accordingly lets you perform the addition correctly.

In the context of the other options, reducing fractions typically applies to simplifying fractions before or after performing operations but does not directly pertain to the initial steps of adding them. Similarly, multiplying fractions is a completely different operation and isn't part of the process of addition. Lastly, adding the numerators without first establishing a common denominator would lead to incorrect results, as the fractions would not accurately represent their respective parts of a whole.