Question

Adding/Subtracting Fractions - we need a _______________

Example:
Adding/Subtracting expressions - we need
______________

Example:
Adding/Subtracting in SN - we need
______________

Example:

Answer 1

Here are the completions for your examples:

1. Adding/Subtracting Fractions - we need a **common denominator**.

2. Adding/Subtracting expressions - we need **like terms**.

3. Adding/Subtracting in Scientific Notation (SN) - we need **the same exponent**.

If you need further details or examples, feel free to ask!