In Exercises 1–10, use the data in the accompanying table and express all results in decimal form. (The data are from “Mortality Reduction with Air Bag and Seat Belt Use in Head-On Passenger Car Collisions,” by Crandall, Olson, and Sklar, American Journal of Epidemiology, Vol. 153, No. 3.) Drivers Involved in Head-On Collision of Passenger Cars.

Drivers Involved in Head-On Collision of Passenger Cars

	Driver Killed	Driver Not killed
Seatbelt Used	3655	7005
Seatbelt not Used	4402	3040

Seatbelt Use If one driver is randomly selected, find the probability he or she was using a seatbelt

The data for drivers involved in a head-on collision is provided for passenger cars.

Probability is defined as the statistical measure that can be used to quantify the risk chances associated withany event.

Mathematically, it is the ratio of the favorable outcomes (to the event) and the total outcomes feasible.

The totals are computed as the additive sum of the row and column values as follows:

Define E as the event that a randomly selected driver uses a seatbelt.

The favorable number of drivers who use a seatbelt is 10660.

The total number of drivers surveyed is 18102.

The probability that a randomly selected driver uses a seatbelt is:

$$\begin{gathered} P\left(E\right)=\frac{10660}{18102} \\ =0.589 \end{gathered}$$

Thus, the probability that the randomly selected driver uses a seatbelt is 0.589.