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Statistical inference — Question 17

QCAA 2022, Paper 2 · 6 marks

Q17 · 2022 · Technology-activeComplex familiar6 marks

QUESTION 17 (6 marks)

The mass of a population of elephants is known to be normally distributed. A biologist randomly selects a number of elephants from this population and measures their masses. The mean mass of the sample is 5206 kg with a standard deviation of 356 kg. The biologist uses the data to calculate a 90% confidence interval for the population mean mass of (5159.1,5252.9)(5159.1,5252.9) kg. Determine a 99% confidence interval for the population mean mass based on the same data.
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