An HR manager of a company finds that teenagers frequently change jobs. The dissatisfaction with their present jobs is a major factor in the decision they make.

Thus, she selects a sample of interviews of 15 teenagers from the past six months. She records the number of months the teenagers spent on their previous jobs:

12 5 1 6 20 24 16 7 11 8 23 19 25 14 4

a. Calculate the range of months that the teenagers spent on their jobs.

b. Calculate the median months that each spent at their previous job.

c. Calculate the interquartile range for the months each teenager spent at his or her previous job.

d. Construct a grouped data frequency distribution for the months the teenagers spent at their previous job.

e. Use the frequency distribution in part d to construct a histogram.

f. Develop a box and whisker plot for the data.

g. Suppose the HR manager decides to employ the teenagers who worked longer than 90th percentiles of months from her sample. Determine the minimum number of months each teenager should have worked to gain employment in this company.