In: Statistics and Probability
a) A county clerk wants to estimate the proportion of voters who will need special election facilities. Suppose a sample of 400 voters was taken. If 150 need special election facilities, what is the upper confidence limit (UCL) for the 90% confidence interval for the population proportion of voters who will need special election facilities. Round your answer to 3 decimal places.
b) A hotel chain wants to estimate the mean number of rooms rented daily in a given month. The population of rooms rented daily is assumed to be normally distributed for each month with a standard deviation of 240 rooms. During February, a sample of 25 days has a sample mean of 370 rooms.
What is the upper confidence limit (UCL) of the 99% confidence interval for the mean number of rooms rented daily in a given month? Round your answer to the nearest whole number.