Ctrl+k

Identify one third

One third, written 13\frac{1}{3}, is one of three equal parts of a whole; the denominator indicates the three equal parts, and the numerator identifies one part. The idea applies to regions, lengths, and collections when the whole is partitioned equally, and supports recognizing that three one-thirds make one whole; unequal parts do not represent thirds.

Detailed Explanation: 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 33 parts.
  2. Choose one of those parts.
  3. Write the fraction as 13\frac{1}{3}:
    • The bottom number, 33, tells how many equal parts there are.
    • The top number, 11, tells how many parts we have.

Example: A rectangle is split into 33 equal parts, and 11 part is shaded.

The whole rectangle has 33 equal parts, and 11 part is shaded. Therefore, the shaded part is

13\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.

Learn by doing: Identify one third

Click a topic below to practice the foundational skills you'll need, learn the steps, or master this skill

    Practice with unlimited practice problems

    Fractions Thirds - Which Set Makes a Whole

      ?