# Find Part I II, below,

Excel Activity #3 — Chapter 6
Instructions: Find Part I & II, below, utilizing Excel and the Excel skills you ascertained from
STAT 1102. Print your results in a well formatted professional manner. All formulas/equations
utilized within Excel need be pasted within a Word Document, printed, and submitted with your
Excel results (i.e. if you instructed a specific cell within Excel to make a specific calculation, for
example Cell C2 is set to “=AVERAGE(range…)”, then on a Word Doc list:
1.Cell C2 = “=AVERAGE(range…)”
2. ……
3. …… etc….
Part I—Data in “Texts & Snaps” Tab
Suppose we are interested in the average number of texts and snapchats sent by Temple
students before 8am. The sample data collected is under the “Texts & Snaps” tab.
1. Create a 90%, 95%, and 99% confidence interval for the true average number of texts
sent before 8am.
2. Create a 90%, 95%, and 99% confidence interval for the true average number of
snapchats sent before 8am.
Part II—Data in “Work & Workout” Tab
Suppose we are interested in the average number of hours Temple students work at a job
and workout each week. The sample data collected is under the “Work & Workout” tab.
1. Create a 90%, 95%, and 99% confidence interval for the true average number of work
hours (WorkHours column).
2. Create a 90%, 95%, and 99% confidence interval for the true average number of hours
that students workout (Workout column).
Part III—No Excel, Use sample size formula!
1. You plan to perform another survey to estimate the average number of texts sent by
Temple students before 8am. This time, you want to be 95% confident that mean is
within ±1. What sample size do you use?
2. You plan to perform another survey to estimate the average number of hours Temple
students work at a job each week. This time, you want to be 90% confident that mean is
within ±3. What sample size do you use?