The amount of time spent per week in studying STA 392 is of interest. A random sample of 15 students are recorded: (in hours)
4.5 6.8 5.4 6.2 5.6 8.1 3.2 7.3 7.2 6.4 5.3 4.2 6.5 6.0 7.5
Assume the amount of time spent in STA 392 is normally distributed.
Use Statistics software to answer the following two questions.
(a) Find a 90% confidence interval for estimating the true average time spent in STA 392.
(b) Find a 99% confidence interval for estimating the true average time spent in STA 392.