Edexcel S4 2006 June — Question 1

Exam BoardEdexcel
ModuleS4 (Statistics 4)
Year2006
SessionJune
TopicHypothesis test of a normal distribution

  1. Historical records from a large colony of squirrels show that the weight of squirrels is normally distributed with a mean of 1012 g . Following a change in the diet of squirrels, a biologist is interested in whether or not the mean weight has changed.
A random sample of 14 squirrels is weighed and their weights \(x\), in grams, recorded. The results are summarised as follows: $$\Sigma x = 13700 , \quad \Sigma x ^ { 2 } = 13448750 .$$ Stating your hypotheses clearly test, at the \(5 \%\) level of significance, whether or not there has been a change in the mean weight of the squirrels.