Topics / Statistics / Statistics
OCR Foundation · Paper 1 · May 2025 · Q11 · calculator
Find the Missing Number from the Mean
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From the paper · Q11 · 3 marks
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Three numbers: 6 9 12 A fourth number is added. The mean of the four numbers is 10. Work out the fourth number.
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Total = 4 × 10 = 40. The fourth number = 40 − 27 = 13.
