We are given a two-way probability table
Part a)
If one of the vehicles is selected at random, determine the probability that the vehicle is a car.
From the table, we see that the total number of cars are 1441
Also, the total number of vehicles is 2420
Then the probability of selecting a car is
[tex]P(car)=\frac{1441}{2420}=0.5955[/tex]
Therefore, the probability that the vehicle was a car is found to be 0.5955
Part b)
If one of the vehicles is selected at random, determine the probability that it used the electronic toll pass, given that it was a car.
This is a conditional probability problem.
The conditional probability is given by
[tex]P(used\: |\: car)=\frac{n(used\: and\: car)}{n(car)}[/tex]
From the table, we see that,
[tex]\begin{gathered} n(car\: and\: used)=537 \\ n(car)=1441 \end{gathered}[/tex]
So, the probability is
[tex]\begin{gathered} P(used\: |\: car)=\frac{n(used\: and\: car)}{n(car)} \\ P(used\: |\: car)=\frac{537}{1441} \\ P(used\: |\: car)=0.3727 \end{gathered}[/tex]
Therefore, the probability that it used the electronic toll pass, given that it was a car is found to be 0.3727