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Statistical inference — Question 5

QCAA 2022, Paper 2 · 1 mark

Q5 · 2022 · Technology-activeSimple familiar1 mark

QUESTION 5

A random sample of the petrol price per litre at 50 petrol stations produced a sample mean of $1.52\char36 1.52 and a standard deviation of $0.14\char36 0.14. Based on this sample and using a zz-value of 1.5, an approximate confidence interval for μ\mu is
(A)
($1.47,  $1.57)(\char36 1.47,\;\char36 1.57)
(B)
($1.48,  $1.56)(\char36 1.48,\;\char36 1.56)
(C)
($1.49,  $1.55)(\char36 1.49,\;\char36 1.55)
(D)
($1.50,  $1.54)(\char36 1.50,\;\char36 1.54)
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