Question

question #10 of 10
when you add or subtract fractions, the
--------------------------- must stay the same.
denominator
numerator

Explanation:

To add or subtract fractions, we need a common denominator. When the denominators are the same, we only operate on the numerators (add or subtract them) while keeping the denominator unchanged. For example, $\frac{1}{5} + \frac{2}{5} = \frac{1 + 2}{5}=\frac{3}{5}$, here the denominator 5 stays the same. If denominators are different, we find a common denominator first (like converting $\frac{1}{2}$ and $\frac{1}{3}$ to $\frac{3}{6}$ and $\frac{2}{6}$) and then add/subtract, still keeping the denominator (now 6) the same during the operation. So the term that must stay the same is the denominator.

Answer:

denominator