A) Construct a 99% confidence interval to estimate the population mean using the data below.
x̄ = 54
σ = 10
n = 39
With 99% confidence, when n = 39, the population mean is between a lower limit of ____ and an upper limit of ____
B) Construct a 95% confidence interval to estimate the population mean using the following data. What assumptions need to be made to construct this interval?
x̄ = 83
σ = 20
n = 23
What assumptions need to be made to construct this interval?
A. The population must be normally distributed.
B. The sample size is less than 30.
C. The population is skewed to one side.
D. The population mean will be in the confidence interval
C) Banking fees have received much attention during the recent economic recession as banks look for ways to recover from the crisis. A sample of 32 customers paid an average fee of $12.19 per month on their interest-bearing checking accounts. Assume the population standard deviation is $1.93.
Complete parts a and b below.
a. Construct a 99% confidence interval to estimate the average fee for the population. The 99% confidence interval has a lower limit of ____ and an upper limit of ____
D) Golf cart attendants at a local country club often receive tips from golfers they assist with golf clubs. To help recruit new employees, the country club would like to determine the average tips per day an attendant earns. A sample of 16 attendants averaged $35.73 per day in tips. Assume the population standard deviation for daily tips is $9.48
Complete parts a and b below.
a. Construct a 98% confidence interval to estimate the average daily tips for an attendant. The average daily tips for an attendant is between a lower limit of ____ and an upper limit of ____
E) Construct a 90% confidence interval to estimate the population mean using the data below.
x̄ = 23
s = 4.1
n = 24
What assumptions need to be made about this population?
The 90% confidence interval for the population mean is from a lower limit of ___ and an upper limit of ____