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0580/12 Oct/Nov 2025, Question 7: Basic Probability

Cambridge IGCSE Mathematics 0580 · Paper 12 (Core) · Non-calculator · 3 marks

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The question, in short

A bag holds discs numbered 1 to 8; one disc is drawn at random. On a probability scale from 0 to 1, mark arrows for three events.

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

Part (a) · 1 mark

Draw and label arrow A on the scale for the probability that the chosen number is even.

  1. 1Even numbers: 2, 4, 6, 8, so P = 4/8 = 0.5
  2. 2Draw arrow A at 0.5 (the 4th mark)

AnswerArrow labelled A on 0.5

Part (b) · 1 mark

Draw and label arrow B on the scale for the probability that the chosen number is 9.

  1. 1No disc shows 9, so P = 0
  2. 2Draw arrow B at 0

AnswerArrow labelled B on 0

Part (c) · 1 mark

Draw and label arrow C on the scale for the probability that the chosen number is less than 3.

  1. 1Less than 3: 1, 2, so P = 2/8 = 0.25
  2. 2Draw arrow C at 0.25 (the 2nd mark)

AnswerArrow labelled C on 0.25

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