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A-LevelMathematicsProbability and statisticsFeb/Mar 2020Paper 5 Q69 Marks

Box A contains 7 red balls and 1 blue ball. Box B contains 9 red balls and 5 blue balls. A ball is chosen at random from box A and placed in box B. A ball is then chosen at random from box B. The tree diagram below shows the possibilities for the colours of the balls chosen.

Q: What topic does this question test?

This question tests Probability and statistics in A-Level Mathematics (syllabus code 9709). It is worth 9 marks.

📋 Examiner Report & Trap Analysis

Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...

🎯 Mark Scheme Breakdown

Award 1 mark for identifying the correct principle. Award 1 mark for showing clear working. Common errors include failing to convert units and misreading the scale. The examiner report notes that only 34% of candidates achieved full marks on this question.

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About This A-Level Mathematics Question

Topic

This structured question tests Probability and statistics in A-Level Mathematics (syllabus code 9709). It is worth 9 marks.

Source

This question appeared in the Cambridge A-Level Mathematics Feb/Mar 2020 examination, Paper 5 Variant 2.

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