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4024/22 Oct/Nov 2024, Question 1: Upper and Lower Bounds

Cambridge O Level Mathematics 4024 · Paper 22 (Calculator) · Calculator · 11 marks

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The question, in short

Calculate percentages, ratio shares, proportional costs and bounds from given masses, volumes and ratios in a fruit-and-nut context.

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

Part (a) · 2 marks

Find mango mass as a percentage of total mass using 96 g, 84 g and 60 g.

  1. 1Total mass = 96 + 84 + 60 = 240 g
  2. 284/240 × 100 = 35%

Answer35

Part (b) · 2 marks

Work out juice in millilitres from a 3 : 7 mix totalling 1.4 litres.

  1. 11.4 litres = 1400 ml
  2. 2Juice = 3/(3 + 7) × 1400 = 420 ml

Answer420

Part (c) · 2 marks

Calculate cost for 175 ml given 125 ml costs $1.50 under direct proportion.

  1. 1Cost per ml = 1.50 ÷ 125 = 0.012
  2. 2Cost = 0.012 × 175 = $2.10

Answer2.10

Part (d) · 2 marks

Find nut mass when 285 g raisins make up the remaining 38%.

  1. 1Raisins = 100 − 62 = 38% of the mass, so 1% = 285 ÷ 38 = 7.5 g
  2. 2Nuts = 62 × 7.5 = 465 g

Answer465

Part (e) · 3 marks

Calculate upper and lower bounds of seed mass from 500 g and 350 g rounded values.

  1. 1Total: bounds 495 and 505; nuts: bounds 347.5 and 352.5
  2. 2Upper bound of seeds = 505 − 347.5 = 157.5 g
  3. 3Lower bound of seeds = 495 − 352.5 = 142.5 g

AnswerUpper bound = 157.5, Lower bound = 142.5

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Also searched as: 4024/22/O/N/24 · 4024_w24_qp_22 · 4024 w24 22 · question 1.
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