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Statistical inference — Question 7

QCAA 2020, Paper 2 · 1 mark

Q7 · 2020 · Technology-activeSimple familiar1 mark

QUESTION 7

The heights of all students at a school were measured. A mean height of 157.0157.0 cm was calculated from this data.
A random sample of 3535 students from this school was selected. The mean height of this sample was 159.7159.7 cm with a standard deviation of 8.78.7 cm.
The smallest confidence level that could be used to produce a confidence interval that contains μ\mu, based on this sample, is
(A)
85%85\%
(B)
90%90\%
(C)
95%95\%
(D)
99%99\%
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