Maths GCSE: Fractions, Decimals and Percentages

A guide to converting fractions, decimals and percentages, applied to real-world problems for students struggling to achieve grade 4 pass in GCSE maths.

Looking at key errors highlighted in examiners’ reports, the topic of fractions, decimals and percentages is presented for revision of these key skills looking at calculator and non-calculator approaches.

Matt Parker take students through some of the basics of handling fractions and decimals and percentages, converting between different representations and examining real life applications

This short film is from the BBC series, The Maths Show.

Teacher Notes

Before watching

Ensure students are comfortable with the basic approaches to fractions of an amount and non-calculator questions of percentages of an amount. Explore the difference of simple interest and compound interest.

During watching

Ensure students have a scientific calculator.

Pause the video at key moments and see if your students can work out the calculation which will be explained by Matt. When pausing the video, can students think of other mental or written methods that they prefer? Compare strategies.

Pause at the introduction to compound interest. You may wish to pause and explain in more detail what this term means.

Explore the methods that Matt has shown using the calculator - would students use that method? Some students may use a different approach, elicit confidence in what they % key on the calculator is doing if students use the method shown in the video. Which method links well to non calculator methods?

After watching

Explore different conversions between fractions, decimals and percentages. Students could use a number line, either using notes posted around the room or other active learning techniques. Extend the use of decimals and fractions to include numbers greater than one and negative numbers.

Compound interest has many interesting real-life situations which could be explored, students could investigate different savings options currently available, population growth or half-lives.

Curriculum Notes

Suitable for teaching maths at GCSE in England, Wales and Northern Ireland and National 4/5 or Higher in Scotland.

More from The Maths Show

Algebra and Negative Numbers
Algebra - Formulae and Graphs
Exam Techniques for GCSE Maths
Ratio and Proportion