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Math · Foundational

Ratios & Percentages

The everyday maths of recipes, prices, maps, savings and news headlines. Build intuition for fractions and ratios, recognise proportional and inversely proportional relationships, work with scale drawings, master percentage changes and compound interest, and learn to spot the misleading percentages hiding in adverts and news stories.

9 lessons~45 min0/9 complete
1

Fractions and Ratios

Parts of a whole, and comparisons.

  1. FractionsParts of a whole
  2. Ratios & RatesScaling recipes and best buys
  3. Proportional RelationshipsStraight lines through the origin
  4. Inverse ProportionMore workers, less time
  5. Scale Drawings & MapsLengths, areas and volumes
2

Percentages

Per hundred, changes, interest and traps.

  1. Per HundredPercent of a number
  2. Percent ChangeUp, down, and back again
  3. Interest & CompoundingMoney that grows on itself
  4. Percentage TrapsRead the numbers carefully

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