Question - Travel and Transportation Some researchers believe that the severity of an automobile accident is related to the type of vehicle. For example, pickup trucks tend to be involved in more fatal crashes than other types of vehicles. The following table presents the number of vehicles involved in each type of crash.56 Suppose this table is representative of all crashes in the United States and one crash is selected at random.
|
|
|
Fatal
|
Crash Injury
|
Property
|
|
Vehicle type
|
Passenger car
|
18,350
|
1,506,595
|
3,686,062
|
|
Pickup
|
8,452
|
376,156
|
1,001,893
|
|
Utility
|
6,924
|
447,946
|
1,187,911
|
|
Van
|
2,494
|
174,299
|
453,197
|
|
Other light truck
|
32
|
67,828
|
222,940
|
|
Large truck
|
3,215
|
53,411
|
239,298
|
|
Bus
|
221
|
9,968
|
47,387
|
|
Other
|
1,152
|
6,282
|
12,429
|
a. What is the probability that the crash results in injury only?
b. Suppose the crash involves a utility vehicle. What is the probability that it is fatal?
c. Suppose the crash involves property damage only. What is the probability that the vehicle is a large truck?
d. Suppose the crash is not fatal. What is the probability that it involves a bus?
e. Suppose the crash does not involve a passenger car. What is the probability that it results in injury only?
f. Are the events fatal crash and van independent? Justify your answer.
g. Suppose two crashes are selected at random. What is the probability that both were fatal and involved an unknown type of vehicle?