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Use Excel please.( norm.inv, t.inv, ) QUESTION 2 (a) Suppose that your task is to estimate...

Use Excel please.( norm.inv, t.inv, )

QUESTION 2
(a) Suppose that your task is to estimate the mean of a normally distributed population to within 8 units with 95% confidence and that the population standard deviation is known to be 72. What sample size should be used if you wish to estimate the population mean to within 8 units?
(b) Determine the minimum sample size required for estimating the population proportion of number of people who drive to work, to within 0.002, with 90% confidence.
(c) As a manufacturer of golf clubs, a major corporation wants to estimate the proportion of golfers who are right-handed. How many golfers must be surveyed if they want to be within 0.03 with a 99% confidence level:
i. assuming that there is no information available that could be used as an estimate of p?
ii. assuming that the manufacturer has an estimate of p obtained from a previous study that suggests that 75% of golfers are right-handed?
(d) The population proportion of voters in favour of a particular political

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