A company that tracks the use of its web site determined that the more pages a visitor views, the more likely the visitor are to provide contact information. Use the following tables to answer the questions:
Number of
Pages viewed: 1 2 3 4 or more
Percentage of Visitors: 40 30 20 10
Percentage of visitors In each page-view
Category that provide
Contact information: 10 10 20 40
(a) What is the probability that a visitor to the web site provides contact information?
(b) If a visitor provides contact information, what is the probability that the visitor viewed four or more pages?