MA19-03 Maths Coming soon
Calculate a percentage increase or decrease
MA19-03
This lesson is coming soon.
In this lesson
Find the new value after a percentage increase or decrease by building and applying a single decimal multiplier, including chaining two multipliers for a combined multi-stage change.
What it covers
- Building the decimal multiplier for an increase (100% + r% = multiplier) and a decrease (100% - r% = multiplier)
- Applying that multiplier in one step to find the new value
- Chaining two multipliers together for a combined multi-stage change (e.g. an increase followed by a decrease)
Key words
For: AQA GCSE 8300, Cambridge IGCSE 0580, Edexcel GCSE 1MA1, Edexcel IGCSE 4MA1, Eduqas GCSE C300, OCR GCSE J560
On the specification
| Board | Spec | Statement |
|---|---|---|
| AQA GCSE 8300 | R9 | Define percentage as ‘number of parts per hundred’ |
| Cambridge IGCSE 0580 | C1.13 | Calculate a given percentage of a quantity. |
| Cambridge IGCSE 0580 | E1.13 | Calculate a given percentage of a quantity. |
| Edexcel GCSE 1MA1 | R9 | Define percentage as ‘number of parts per hundred’; interpret percentages and percentage changes as a fraction or a decimal, and interpret these multiplicatively; express one quantity as a percentage of another; compare two quantities using percentages; work with percentages greater than 100%; solve problems involving percentage change, including percentage increase/decrease and original value problems, and simple interest including in financial mathematics |
| Edexcel IGCSE 4MA1 | F1.6E | Solve simple percentage problems, including percentage increase and decrease |
| Eduqas GCSE C300 | FR10 | Define percentage as 'number of parts per hundred'; interpret percentages and percentage changes as a fraction or a decimal, and interpret these multiplicatively; express one quantity as a percentage of another; compare two quantities using percentages; work with percentages greater than 100%; solve problems involving percentage change, including percentage increase / decrease and original value problems, and simple interest including in financial mathematics |
| Eduqas GCSE C300 | HR10 | Define percentage as 'number of parts per hundred'; interpret percentages and percentage changes as a fraction or a decimal, and interpret these multiplicatively; express one quantity as a percentage of another; compare two quantities using percentages; work with percentages greater than 100%; solve problems involving percentage change, including percentage increase / decrease and original value problems, and simple interest including in financial mathematics |
| OCR GCSE J560 | 2.03c | Increase or decrease a quantity by a simple percentage, including simple decimal or fractional multipliers. Apply this to simple original value problems and simple interest. |
For teachers
This GCSE Maths lesson teaches calculate a percentage increase or decrease. By the end, students should be able to find the new value after a percentage increase or decrease by building and applying a single decimal multiplier, including chaining two multipliers for a combined multi-stage change. It works through three worked examples and the mistakes examiners report.