It is claimed that a car has travelled on average more than 20000 kilometres per year. To test this claim, a random sample of 30 car owners have been selected. The owners were asked to keep records on...

Extracted text: It is claimed that a car has travelled on average more than 20000 kilometres per year. To test this claim, a random sample of 30 car owners have been selected. The owners were asked to keep records on the number of kilometres they have travelled. Would you agree with this claim if the random sample shows an average of 22500 kilometres and a standard deviation of 5500 kilometres? Use 0.05 level of significance to justify your answer.