a. What is a random variable?

b. What is a probability distribution?

c. A graph in USA Today listed the percentages for the number of days in a week that American adults cook at home in an average week. For example, 13% of American adults cook at home 3 days in an average week. The accompanying table is based on the graph. Does this table describe a probability distribution? Why or why not?

d. Assuming that the table does describe a probability distribution, find its mean.

e. Assuming that the table does describe a probability distribution, find its standard deviation.

f. Is it unusual to randomly select an adult American and find that he or she does not cook at home in an average week? Why or why not?