1) The Franklin Tire Company is interested in demonstrating the durability of its steel-belted radial tires. To do this, the managers have decided to put four tires on 100 different sport utility vehicles and drive them throughout Alaska. The data collected indicate the number of miles (rounded to the nearest 1,000 miles) that each of the SUVs traveled before one of the tires on the vehicle did not meet minimum federal standards for tread thickness. The data file is called Franklin.
a. Construct a frequency distribution and histogram using eight classes. Use 51 as the lower limit of the first class.
b. The marketing department wishes to know the tread life of at least 50% of the tires, the 10% that had the longest tread life, and the longest tread life of these tires. Provide this information to the marketing department. Also provide any other significant items that point out the desirability of this line of steel-belted tires.
c. Construct a frequency distribution and histogram using 12 classes, using 51 as the lower limit of the first class. Compare your results with those in parts a and b. Which distribution gives the best information about the desirability of this line of steel-belted tires? Discuss.
Orlando, Florida, is a well-known, popular vacation destination visited by tourists from around the world. Consequently, the Orlando International Airport is busy throughout the year. Among the variety of data collected by the Greater Orlando Airport Authority is the number of passengers by airline. The file Orlando Airport contains passenger data for December 2011. Suppose the airport manager is interested in analyzing the column labeled “Total” for this data.
a. Using the 2k ≥ n guideline, what is the minimum number of classes that should be used to display the data in the “Total” column in a grouped data frequency distribution?
b. Referring to part a, what should the class width be, assuming you round the width up to the nearest 1,000 passengers?
c. Referring to parts a and b, develop a grouped data frequency distribution for these airport data.
d. Based on your answer to part c, construct and interpret a frequency histogram for the data.
The manager of AJ’s Fitness Center, a full-service health and exercise club, recently conducted a survey of 1,214 members. The objective of the survey was to determine the satisfaction level of his club’s customers. In addition, the survey asked for several demographic factors such as age and gender. The data from the survey are in a file called AJFitness.
a. One of the key variables is “Overall Customer Satisfaction.” This variable is measured on an ordinal scale as follows:
5 = very satisfied 4 = satisfied 3 = neutral 2 = dissatisfied 1 = very dissatisfied
Develop a frequency distribution for this variable and discuss the results.
b. Develop a joint relative frequency distribution for the variables “Overall Customer Satisfaction” and “Typical Visits Per Week.” Discuss the results.