Reports from a new system set up to
monitor Internet use by company employees indicate that 145 out of a random
sample of 1100 employees at a corporation accessed internet sites that were
clearly not related to their jobs over the last week. On average, employees who
accessed non job related sites spent 4.8 hours per week at such sites with a
standard deviation of 2.1 hours
a. Give a 95% confidence interval for the percentage of employees at the
corporation who access non-job related sites.
b. Briefly explain in one short sentence how to interpret this interval.
c. Statistics show that about 103 of
people nationwide access non-job related sites at work. Is this company really
any different from the national statistics?
d. Can we say that roughly 953 of people at this company spent in the range of
4.8 hours plus or minus 4.2 hours on non job-related web sites?