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A-LevelMathematicsProbability and statisticsMay/June 2025Paper 6 Q44 Marks

A biased spinner has four sides. Each side is of a different colour: yellow, red, green or black. The probability, p, that the spinner will land on red is unknown. The spinner was spun 200 times, and the proportion, a, of times that it landed on red was noted. This proportion was used to calculate an approximate 90% confidence interval for p. The width of this confidence interval was 0.1066 correct to 4 significant figures. Find the two possible values of a.

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The correct answer is . This question tests the candidate's understanding of probability and statistics within the Mathematicssyllabus. The examiner's mark scheme requires...

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About This A-Level Mathematics Question

This structured question appeared in the Cambridge A-Level Mathematics (9709) May/June 2025 examination, Paper 6 Variant 2. It tests the topic of Probability and statistics and is worth 4 marks.

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