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0580/33 Oct/Nov 2023, Question 4: Pie Charts

Cambridge IGCSE Mathematics 0580 · Paper 33 (Core) · Calculator · 13 marks

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The question, in short

Glass-making question: complete a proportion table and pie chart, use ratios, scale soda to silica, apply M = 2.5 × A × T, write a large number in standard form, and compare recycling bars.

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

Part (ai) · 2 marks

Complete the table by working out the missing pie chart sector angles for soda and for lime and magnesia.

  1. 175% ↔ 270°, so 1% ↔ 3.6°
  2. 2Soda = 15 × 3.6 = 54°
  3. 3Lime and magnesia = 10 × 3.6 = 36°

Answer| Soda | 54° | | Lime and magnesia | 36° |

Part (aii) · 1 mark

Complete the pie chart by drawing the sectors for soda and for lime and magnesia.

  1. 1Split the blank 90° into sectors of 54° (Soda) and 36° (Lime and magnesia)
  2. 2Measure 54° from the edge of the Silica sector with a protractor, draw the radius and label both sectors

AnswerCorrect pie chart

Part (aiii) · 1 mark

Given lime : magnesia = 3 : 2, find the percentage of total mass that is magnesia.

  1. 1Magnesia = 2/(3 + 2) × 10% = 4%

Answer4

Part (aiv) · 2 marks

Given 8.25 kg of soda, work out the mass of silica used, in kilograms.

  1. 115% ↔ 8.25 kg, so 1% ↔ 8.25 ÷ 15 = 0.55 kg
  2. 2Silica = 75 × 0.55 = 41.25 kg

Answer41.25

Part (b) · 2 marks

Use M = 2.5 × A × T to calculate the mass of a 1.9 m by 0.6 m sheet that is 8 mm thick.

  1. 1A = 1.9 × 0.6 = 1.14 m²
  2. 2M = 2.5 × 1.14 × 8 = 22.8 kg

Answer22.8

Part (c) · 1 mark

Write 130 000 000 tonnes in standard form.

  1. 1130 000 000 = 1.3 × 10⁸

Answer1.3 × 10⁸

Part (di) · 2 marks

Complete the bar chart by adding bars for glass at target 55% and actual 70%.

  1. 1In the Glass row, draw a shaded (target) bar to 55%
  2. 2Below it draw an unshaded (actual) bar to 70%

AnswerCorrect bars drawn

Part (dii) · 2 marks

Identify which materials were recycled at more than double their target rate.

  1. 1Double each target rate and compare it with the actual rate.
  2. 2Metal: actual 30 is below target 70, so no.
  3. 3Paper & cardboard: 85 < 2 × 60 = 120, so no.
  4. 4Plastic: 47.5 > 2 × 22.5 = 45. Wood: 35 > 2 × 15 = 30.
  5. 5Answer: Plastic, Wood

AnswerPlastic, Wood

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Also searched as: 0580/33/O/N/23 · 0580_w23_qp_33 · 0580 w23 33 · question 4.
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