Basic 3 · Mathematics · Fractions

Comparing and Ordering Fractions

In this topic you will compare and order unit fractions and fractions with the same denominator.

By the end of these notes you should be able to:

  • Compare unit fractions
  • Compare fractions with the same denominator
  • Order fractions on a number line

What you already know

  • Understanding fractions

Copy everything that has a blue line on its left into your notebook. The other parts are for reading.

Strand
Number
Sub-strand
Fractions
Indicator
B3.1.3.1.3 – Compare and order unit fractions and fractions with like denominators by using concrete models pictorial representations and number line

Introduction

Would you rather have ½ of an orange or ¼ of the same orange? The more equal parts there are, the smaller each part is.

1. Comparing Unit Fractions

The bigger the denominator, the smaller the part.

½ > ⅓ > ¼ > ⅕

A fraction wall comparing ½, ⅓, ¼ and ⅕
Figure 1: Comparing unit fractions Copy the fraction wall.Illustration: Sirbus

2. Same Denominator

When the denominators are the same, compare the numerators.

⅘ > ⅗ > ⅖ > ⅕

3. Fractions on a Number Line

On a line from 0 to 1 cut into 4 equal parts: 0, ¼, ²⁄₄, ¾, 1.

Example

Order from smallest to largest: ⅔, ⅓, 3/3.

  1. Same denominator (3), so compare numerators: 1, 2, 3.

Answer: ⅓, ⅔, 3/3

Remember: 3/3 is one whole.

New words

compare
To find which is bigger or smaller.
order
To arrange by size.
number line
A line with numbers in order.
like denominators
Fractions with the same bottom number.

Summary

  • For unit fractions, a bigger denominator means a smaller part.
  • With the same denominator, compare the numerators.
  • Fractions can be shown on a number line.

Class activity: Fraction Line

  1. Draw a number line from 0 to 1 with chalk.
  2. Mark quarters on it.
  3. Place fraction cards in the right places.

You need: Fraction strips cut from old cartons, Bottle tops, Exercise books

Exercises

Answer in your exercise book first, then check your answers.

  1. 1. Which is bigger?

    • A. ½
    • B. ¼
    • C. ⅕
    • D. ⅙
    Show answer
    Answer: ½Fewer parts means bigger parts.
  2. 2. Which is the smallest?

    • A. ⅙
    • B. ⅓
    • C. ½
    • D. ¼
    Show answer
    Answer: ⅙The biggest denominator gives the smallest part.
  3. 3. ¾ > ¼

    • A. True
    • B. False
    Show answer
    Answer: True3 quarters is more than 1 quarter.
  4. 4. ⅕ > ⅓

    • A. True
    • B. False
    Show answer
    Answer: False⅓ is bigger because the whole is cut into fewer parts.
  5. 5. 4/4 = ______ whole

    Show answer
    Answer: 1Four quarters make one whole.
  6. 6. Order from largest to smallest: ¼, ½, ⅓.

    Show answer
    Answer: ½, ⅓, ¼Smaller denominators give bigger parts.

Homework

  1. Fold three paper strips into halves, thirds and quarters. Compare one part of each.