Answer:
There is a 6.07% probability that during next 2 min exactly 5 cars passing an intersection are from state.
Step-by-step explanation:
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
In which
x is the number of sucesses
[tex]e = 2.71828[/tex] is the Euler number
[tex]\mu[/tex] is the mean in the given time interval.
In this problem, we have that:
A traffic engineer monitors the traffic flowing through an intersection with an average of 6 cars per minute. So in 2 minutes, 12 cars are expected to flow through the intersection.
If 75% of vehiclesare from state, what is the probability that during next 2 min exactly 5 cars passing an intersection are from state?
We want to know how many of these cars are from state. In 2 minutes, 0.75*12 = 9 cars from the state are expected to pass the intersection, so [tex]\mu = 9[/tex].
We want to find P(X = 2).
[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]
[tex]P(X = 5) = \frac{e^{-9}*9^{5}}{(5)!} = 0.0607[/tex]
There is a 6.07% probability that during next 2 min exactly 5 cars passing an intersection are from state.