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A-LevelMathematicsProbability and statisticsOct/Nov 2020Paper 5 Q46 Marks

The random variable X takes each of the values 1, 2, 3, 4 with probability ¹/₄. Two independent values of X are chosen at random. If the two values of X are the same, the random variable Y takes that value. Otherwise, the value of Y is the larger value of X minus the smaller value of X.

Q: What topic does this question test?

This question tests Probability and statistics in A-Level Mathematics (syllabus code 9709). It is worth 6 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 6 marks.

Source

This question appeared in the Cambridge A-Level Mathematics Oct/Nov 2020 examination, Paper 5 Variant 1.

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