Skill: Identify one fourth

A fourth is one of four equal-sized parts of a whole. We write one fourth as $\frac{1}{4}$.

Example: Which fraction of the rectangle is part C?

+-----+-----+-----+-----+
|  A  |  B  |  C  |  D  |
+-----+-----+-----+-----+

1. Look at the whole rectangle.
2. Count the equal parts: there are $4$ parts.
3. Part C is just $1$ of those parts.
4. So part C is $\boxed{\frac{1}{4}}$ of the rectangle.

All four parts together make the whole:
$\frac{1}{4}+\frac{1}{4}+\frac{1}{4}+\frac{1}{4}=1$.

Remember: the parts must be equal-sized. If one part is larger than the others, it is not a fourth.