Maths · KS3 Y7 · Number

Estimating before calculating

m32Free1:00Heddy Score 2 of 7, below the standard

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What you need to know

Round each number to one significant figure to estimate.
An estimate gives a quick check on a calculator answer.
Say whether the estimate is likely to be too high or too low.

In this clip

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26:07–26:52Laws of indicesm41

26:52–27:39Fractional indicesmh6

27:39–29:21The product rule for countinggcse-math-n5b

29:21–31:24Error intervalsmh5

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59:32–62:40nth term of linear sequencesm70

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97:23–99:36Bearingsm134

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Heddy Score2/7, Below the standard

Trusted source · passed. The creator's own upload, live and playable here.
On the map · not judged yet. A teacher watched it: it mainly teaches this map topic.
Spec-true · not judged yet. Accurate, and right for the current UK specification.
Focused · passed. One idea, short enough to watch in one go.
Accessible · not judged yet. Good captions, clear sound and pictures.
Safe for children · not judged yet. Right for 11 to 16 year olds, with no sales pitch.
Proven · not judged yet. Earned from our students: they learn from it, find it helpful and watch it to the end.

★ passed · ☆ pending · ✕ failed

Our students

Not enough students yet

Our own students' answers. These are what move ★7 Proven.

How the Heddy Score works

Why we picked it

Crossover non-calculator revision built around the May 2023 Paper 1; suits Year 10–11 students on either tier aiming for grade 5.

The GCSE Maths Tutor on YouTubechecked 2026-10-16