Reverse Percentages (No Calculator) — KS3 Maths
A clear, step-by-step KS3 lesson on reverse percentages: find the original amount after a percentage change. Spot what % you're given, find 1%, then times by 100 — with a bar model, no calculator needed.
A jacket is £160 in a 20% off sale — what was the original price? Reverse percentages work backwards: the amount you're given is (100 ± the change)% of the original, so find 1% by dividing, then multiply by 100. This lesson uses a bar model to show why a 20% discount leaves 80% and a 10% rise gives 110%, works through three examples (a sale, a pay rise and a harder sale), flags the classic mistake, and finishes with a quick quiz — all without a calculator.
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A free printable worksheet with 16 questions and a full worked answer key. No sign-up needed.