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4024/11 Oct/Nov 2023, Question 12: Scale Drawings

Cambridge O Level Mathematics 4024 · Paper 11 (Non-calculator) · Non-calculator · 5 marks

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The question, in short

Using a 1 : 20 000 scale drawing of boats A and B, find the real distance in kilometres, construct the equidistant locus, and locate ship S.

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

Part (a) · 2 marks

Measure the drawn length AB and convert using the scale 1 : 20 000 to give the actual distance in kilometres.

  1. 1Measure AB on the drawing: 8.8 cm to 9.2 cm
  2. 2Actual = (8.8 to 9.2) × 20 000 cm = 176 000 to 184 000 cm
  3. 3= 1.76 to 1.84 km

Answer1.76 to 1.84

Part (b) · 2 marks

With compasses and straight edge only, construct the perpendicular bisector of the line joining A and B.

  1. 1With centre A and then centre B, draw arcs of the same radius (more than half of AB) crossing on both sides of AB
  2. 2Rule a line through the two crossing points: the perpendicular bisector of AB

AnswerAcceptable bisector of AB with correct arcs

Part (c) · 1 mark

Mark S where the perpendicular bisector meets the bearing 105° line from A, then label it.

  1. 1Draw a line from A on a bearing of 105° (105° clockwise from North)
  2. 2S is where this line meets the perpendicular bisector; label it S

AnswerS marked on a bearing of 105° from A and on their bisector

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Also searched as: 4024/11/O/N/23 · 4024_w23_qp_11 · 4024 w23 11 · question 12.
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