CAIE S2 2020 June — Question 1

Exam BoardCAIE
ModuleS2 (Statistics 2)
Year2020
SessionJune
TopicMeasures of Location and Spread
TypeStandard unbiased estimates calculation

1 The lengths, \(X\) centimetres, of a random sample of 7 leaves from a certain variety of tree are as follows.
3.9
4.8
4.8
4.4
5.2
5.5
6.1
  1. Calculate unbiased estimates of the population mean and variance of \(X\).
    It is now given that the true value of the population variance of \(X\) is 0.55 , and that \(X\) has a normal distribution.
  2. Find a 95\% confidence interval for the population mean of \(X\).