Skill: Identify one third

A third means one of three equal parts.

To identify one third:

1. Count how many equal parts make the whole. There must be $3$ parts.
2. Choose one of those parts.
3. Write the fraction as $\frac{1}{3}$:
   • The bottom number, $3$, tells how many equal parts there are.
   • The top number, $1$, tells how many parts we have.

Example: A rectangle is split into $3$ equal parts, and $1$ part is shaded.

The whole rectangle has $3$ equal parts, and $1$ part is shaded. Therefore, the shaded part is

$$\frac{1}{3}$$

It is one third of the rectangle. Three equal one-thirds make one whole. If the parts are not equal, they are not thirds.