GCSE · Direct & inverse proportion

Proportion with squares, cubes and rootsExam-style questions

Why y ∝ x², y ∝ √x and y ∝ 1/x² all follow the same three-step method — write the equation, find k, use it — and how the power changes the scaling.

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12 questions · GCSE (Higher) level · mark scheme and worked solution on each · no sign-up to try

DifficultyAllLevel 2Level 3Level 4Level 5
  1. 1
    yy is directly proportional to x2x^2.

    When x=2x = 2, y=12y = 12

    Work out the value of yy when x=5x = 5 [3]
    Level 2 · 3 marksTry it