The heights of UNC sophomores are approximately normallydistributed. The heights in inches of 8 randomly selectedsophomores are shown below. Use these heights to find a 95%confidence interval for the average height μ of UNC sophomores.Give the endpoints of your interval to one decimal place.
72, 69, 70, 68, 70, 66, 75, 64
a) Use these heights to find a 95% confidence interval for theaverage height μ of UNC sophomores. Give the endpoints of yourinterval to one decimal place.
95% confidence interval: (  ,  )
b) Using the 8 data points above, conduct a test of followinghypotheses at level of significance α=0.05:
H0: μ = 67; Ha: μ > 67
Find the sample mean x, the sample standard deviation s, theappropriate t-statistic and p-value. Use Excel when necessary andgive all answers to four decimal places.
Sample mean =Â Â
Sample standard deviation =Â Â
t =Â Â
p=
