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0580/22 Oct/Nov 2025, Question 16: Interior and Exterior Angles of Polygons

Cambridge IGCSE Mathematics 0580 · Paper 22 (Extended) · Non-calculator · 4 marks

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The question, in short

Two regular polygons share side AB; BD and BC are other sides meeting at B with angle DBC = 14°. Find n, the number of sides of the polygon containing AB and BC.

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

Solution · 4 marks

  1. 1Exterior angle of 15-sided polygon = 360 ÷ 15 = 24°
  2. 2Exterior angle of n-sided polygon = 24 − 14 = 10°
  3. 3n = 360 ÷ 10 = 36

Answer36

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Also searched as: 0580/22/O/N/25 · 0580_w25_qp_22 · 0580 w25 22 · question 16.
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