Ratios and proportion.
Compare relative amounts, scale equivalent ratios, share totals and decide when proportional models make sense.
Work through the topic
Learn the method, follow the examples, then try the worksheet.
- 01
Ratio notation and part-to-part/whole meaning
Read a ratio in the stated order and distinguish comparing two parts from comparing a part with the whole.
- 02
Equivalent ratios and simplest form
Scale or simplify all entries together and recognise whether two ratios describe the same relative amounts.
- 03
Dividing an amount in a ratio
Use the total number of ratio parts to share a fixed amount in the required proportions.
- 04
Scaling recipes and mixtures
Keep a recipe or mixture in proportion by scaling every ingredient by the same factor.
- 05
Ratio tables
Use tables to organise equivalent pairs and identify a constant unit value.
- 06
Choosing, checking and explaining proportional models
Use data and context to choose a proportional model and explain where its predictions are reasonable.
Topic review
Revisit the key ideas, then choose a practice paper.