Exercises  for the mean (unknown standard deviation or sample size less than 30)
1. Find the values for each.
a. ta/2 and n=18 for 99% confidence interval for the mean
b. ta/2 and n= 23 for 95 % confidence interval for the mean
c. ta/2 and n= 15 for 98% confidence interval for the mean
d. ta/2 and n= 10 for 90% confidence interval for the mean
e. ta/2 and n= 20 for 95% confidence interval for the mean

2. The average hemoglobin reading for a samp0le of 20 teachers was 16 grams per 100 milliliters, with a sample standard deviation of 2 grams, find the 99% confidence intervals of the true mean.

jorey mark millamena
july 23, 2012