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4024/11 Oct/Nov 2022, Question 5: Estimation

Cambridge O Level Mathematics 4024 · Paper 11 (Non-calculator) · Non-calculator · 4 marks

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The question, in short

Round 306.248 to 2 decimal places and to 2 significant figures, then estimate 9.37² − ∛1046 by rounding each number to 1 significant figure.

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

Part (ai) · 1 mark

Give 306.248 rounded to 2 decimal places.

  1. 1306.248 → 306.25 (third decimal 8 rounds up)

Answer306.25

Part (aii) · 1 mark

Give 306.248 rounded to 2 significant figures.

  1. 1306.248 → 310 (2 s.f.)

Answer310

Part (b) · 2 marks

Estimate 9.37² − ∛1046 by first writing each number correct to 1 significant figure.

  1. 19.37 ≈ 9, 1046 ≈ 1000
  2. 29² − ∛1000 = 81 − 10 = 71

Answer71

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Also searched as: 4024/11/O/N/22 · 4024_w22_qp_11 · 4024 w22 11 · question 5.
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