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0580/11 Oct/Nov 2022, Question 20: Standard Form

Cambridge IGCSE Mathematics 0580 · Paper 11 (Core) · Calculator · 3 marks

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The question, in short

Convert 0.00273 to standard form, then identify two mistakes in Sam's answer of 42.1 × 10⁶ to 9306 × 4532 given to 3 significant figures in standard form.

Summarised in our own words. Use the official paper for the exact wording and any diagrams.

Part (a) · 1 mark

Write 0.00273 in standard form.

  1. 10.00273 = 2.73 × 10⁻³

Answer2.73 × 10⁻³

Part (b) · 2 marks

State the two errors Sam made in his answer 42.1 × 10⁶ for 9306 × 4532, which should be in standard form to 3 significant figures.

  1. 19306 × 4532 = 42 174 792 = 4.22 × 10⁷ (3 s.f.)
  2. 2Error 1: 42.1 is incorrectly rounded to 3 significant figures (should be 42.2)
  3. 3Error 2: 42.1 × 10⁶ is not correct standard form (the first number must be between 1 and 10)

AnswerError 1: 42.1 is incorrectly rounded to 3 significant figures; Error 2: 42.1 × 10⁶ is not correct standard form

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Also searched as: 0580/11/O/N/22 · 0580_w22_qp_11 · 0580 w22 11 · question 20.
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