PricewaterhouseCoopers Saratoga, in its 2005/2006 Human Capital Index Report, indicated the average number of days it took for an American company to fill a job vacancy in 2004 was 48 days. Sample data similar to those used in the study are in a file titled Hired. Categories for the days and hire cost are provided under the headings “Time” and “Cost,” respectively.
a. Calculate the probability that a company vacancy took at most 100 days or cost at most $4,000 to fill.
b. Of the vacancies that took at most 100 days to fill, calculate the probability that the cost was at most $4,000.
c. If three of the vacancies were chosen at random, calculate the probability that two of the vacancies cost at most $4,000 to fill.