4 It is known that the mass of a certain type of lizard has a normal distribution with mean 72.7 g and standard deviation 4.8 g. A zoologist finds a colony of lizards in a remote place and is not sure...

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Extracted text: 4 It is known that the mass of a certain type of lizard has a normal distribution with mean 72.7 g and standard deviation 4.8 g. A zoologist finds a colony of lizards in a remote place and is not sure whether they are of the same type. In order to test this, she collects a sample of 12 lizards and weighs them, with the following results. 80.4 67.2 74.9 78.8 76.5 75.5 80.2 81.9 79.3 70.0 69.2 69.1 (i) Write down, in precise form, the zoologist's null and alternative hypotheses, and state whether a one-tail or two-tail test is appropriate. (ii) Carry out the test at the 5% significance level and write down your conclusion. (iii) Would your conclusion have been the same at the 10% significance level?


Extracted text: 4 (i) Ho:µ = 72.7 g, H,: µ ± 72.7 g; two-tail test. (ii) z= 1.84, not significant (iii) No, significant