As a class project you have been asked to project the proportion of time a professor spends on various activities. You have decided to use the work-sampling method. Your initial observations are shown.

You are instructed that your estimates are to be within 5 percent of the true value with 97 percent confidence (z = 2.17).
(a) Based on your initial observations, how many total observations are needed to estimate the proportion of time the professor spends on each activity?
After taking additional observations, the following data are available.

(b) Determine what proportion of time the professor spends teaching class.
(c) Determine what proportion of time the professor spends working on research.
(d) If the professor works approximately 54 hours per week, determine the amount of time that would normally be spent on eachactivity.

Number of Times Observed Activity Observed Grading Administrative paperwork Preparing for class Teaching class Meeting with student(s) On the phone Working on research Unavailable Total 40 Number of Times Observed 30 50 30 30 Activity Observed Grading Administrative paperwork Preparing for class Teaching class Meeting with student(s) On the phone Working on r Unavailable Total 17 45 34 299