Chapter 4: Fractions, decimals and percentages

Fractions, decimals and percentages can describe the same amount in different forms.

The chapter problem

A music shop offers a £48 keyboard with a discount of $\frac{1}{4}$. A second shop lists the same keyboard at £37.50. Which price is lower, and by how much?

First contact: without working it out, predict which shop has the lower price. You are not being marked. You will return to this problem after learning how fractions and percentages describe amounts.

By the end of this chapter you will be able to

• make equivalent fractions and order fractions, decimals and percentages;
• add, subtract, multiply and divide fractions;
• convert fractions to terminating and recurring decimals;
• use fractions and percentages to find parts, changes and original amounts.

Roadmap

1. 4.1 Equivalent fractions and ordering
2. 4.2 Adding and subtracting fractions
3. 4.3 Multiplying and dividing fractions
4. 4.4 Fractions and terminating decimals
5. 4.5 Recurring decimals — Higher only
6. 4.6 Fractions and percentages as operators
7. Review

Your connection

A fraction or percentage can appear in a price, a recipe, a score or a journey. Where have you or someone you know used one recently? Write one example and say what the number described.