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Brainlag Learn / GCSE Maths

Ratio and proportion

Convert units and use scales, write and simplify ratios, share amounts in a ratio, compare best buys and exchange rates, and solve direct and inverse proportion problems.

Lessons

  1. Units, conversions and scalesChange between metric units of length, mass, capacity, area and volume, work with hours and minutes, and use scale drawings and map scales. 25 min, with the Unit Converter, free
  2. Writing and simplifying ratiosSimplify ratios, including ones with different units, decimals and fractions, write them in the form 1 : n or n : 1, and link ratios with fractions. 25 min, with the Fraction Calculator, free
  3. Sharing and using ratiosShare an amount in a ratio, work from one share or the difference between shares, combine two ratios, and (Higher) solve problems where a ratio changes. 25 min, Plus
  4. Best buys, recipes and exchange ratesCompare value for money with unit prices, scale recipes up and down, find the most a recipe can make, and change money between currencies. 25 min, Plus
  5. Direct and inverse proportionSolve proportion problems with the unitary method and with formulae y = kx and y = k/x, recognise proportion in tables and graphs, and (Higher) work with y ∝ x², y ∝ 1/x² and y ∝ √x. 25 min, with the Graphing Calculator, Plus

Practise and test