Question: A study examined how long aircraft air conditioning units operated after being

repaired. Here are the operating times (in hours) for one unit (Excel exam file;

worksheet Question 1):

a. Make a histogram of these data, using 40 hour wide classes, starting with

0 £ time < 40, 40 £ time < 80, ...

b. Describe the overall shape of the distribution. Is it roughly symmetric, skewed to the

right, or skewed to the left? Are there any outliers?

c. Is the five number summary or the mean and standard deviation a better brief

summary for this distribution? Explain your choice. Calculate the one of these

summaries that you choose.