Is a dog “man’s best friend”? One would think so, with 60 million pet dogs nationwide. But how many friends are needed? In the American Pet Products Association’s 2007–2008 National Pet Owners Survey, the following statistics were reported.
Number of Pet Dogs Percentage
Three or more.......... 12
a. Is this a discrete probability distribution? Explain.
b. Draw a relative frequency histogram to depict the results shown in the table.
c. Replacing the category “Three or more” with exactly “Three,” find the mean and standard deviation of the number of pet dogs per household.
d. How do you interpret the mean?
e. Explain the effect that replacing the category “Three or more” with “Three” has on the mean and standard deviation.