Tree and Venn Diagrams · Exercise 9

Approximately 86.5 percent of Americans commute to work by car, truck, or van. Out of that group, 84.6 percent drive alone and 15.4 percent drive in a carpool. Approximately 3.9 percent walk to work and approximately 5.3 percent take public transportation.

(a) Construct a table or a tree diagram of the situation. Include a branch for all other modes of transportation to work.
(b) Assuming that the walkers walk alone, what percent of all commuters travel alone to work?
(c) Suppose that 1,000 workers are randomly selected. How many would you expect to travel alone to work?
(d) Suppose that 1,000 workers are randomly selected. How many would you expect to drive in a carpool?

OpenStax, Statistics · §3.5 Tree and Venn Diagrams · Exercise 9