Edexcel S3 2022 January — Question 2

Exam BoardEdexcel
ModuleS3 (Statistics 3)
Year2022
SessionJanuary
TopicHypothesis test of a normal distribution

2. Krishi owns a farm on which he keeps chickens. He selects, at random, 10 of the eggs produced and weighs each of them.
You may assume that these weights are a random sample from a normal distribution with standard deviation 1.9 g The total weight of these 10 eggs is 537.2 g
  1. Find a \(95 \%\) confidence interval for the mean weight of the eggs produced by Krishi's chickens. Krishi was hoping to obtain a \(99 \%\) confidence interval of width at most 1.5 g
  2. Calculate the minimum sample size necessary to achieve this.
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