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4024/22 Oct/Nov 2025, Question 15: Upper and Lower Bounds

Cambridge O Level Mathematics 4024 · Paper 22 (Calculator) · Calculator · 4 marks

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The question, in short

A 2.5 kg bag is rounded to the nearest 0.1 kg; find its bounds, then use a box of 8.0 kg to find the upper bound of the total mass with 12 bags.

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Part (a) · 2 marks

State the upper and lower bounds for the 2.5 kg mass rounded to the nearest 0.1 kg.

  1. 1Half of 0.1 kg is 0.05 kg
  2. 2Upper bound = 2.5 + 0.05 = 2.55 kg, lower bound = 2.5 − 0.05 = 2.45 kg

AnswerUpper bound = 2.55, lower bound = 2.45

Part (b) · 2 marks

Find the upper bound of the total mass of the 8.0 kg box holding 12 bags of potatoes.

  1. 1Upper bound of box = 8.05 kg
  2. 2Upper bound of total = 12 × 2.55 + 8.05 = 30.6 + 8.05
  3. 3= 38.65 kg

Answer38.65

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Also searched as: 4024/22/O/N/25 · 4024_w25_qp_22 · 4024 w25 22 · question 15.
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