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4024/21 Oct/Nov 2025, Question 12: Standard form

Cambridge O Level Mathematics 4024 · Paper 21 (Calculator) · Calculator · 3 marks

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The question, in short

Write 0.0142 in standard form. Then find x and y if (3.2 × 10⁻⁴) × (x × 10ʸ) = 2.6 × 10³, with x × 10ʸ in standard form.

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Part (a) · 1 mark

Write 0.0142 in standard form.

  1. 10.0142 = 1.42 × 10⁻²

Answer1.42 × 10⁻²

Part (b) · 2 marks

Find x and y.

  1. 1x × 10ʸ = (2.6 × 10³) ÷ (3.2 × 10⁻⁴)
  2. 2= 0.8125 × 10⁷ = 8.125 × 10⁶
  3. 3x = 8.125, y = 6

Answerx = 8.125, y = 6

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Also searched as: 4024/21/O/N/25 · 4024_w25_qp_21 · 4024 w25 21 · question 12.
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