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A particular intersection in a small town is equipped with a surveillance camera. The number of traffic tickets issued to

drivers passing through the intersection follows the Poisson distribution and averages 5.4 per month.
a. What is the probability that 5 traffic tickets will be issued at the intersection next month?
b. What is the probability that 3 or fewer traffic tickets will be issued at the intersection next month?
c. What is the probability that more than 6 traffic tickets will be issued at the intersection next month?

User Syden
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a. To find the probability that 5 traffic tickets will be issued at the intersection next month, we can use the Poisson distribution formula:

P(X = x) = (e^(-λ) * λ^x) / x!

where λ is the average number of events per unit of time or space. In this case, λ = 5.4 and x = 5. Plugging in these values, we get:

P(X = 5) = (e^(-5.4) * 5.4^5) / 5! = 0.169

Therefore, the probability that 5 traffic tickets will be issued at the intersection next month is 0.169 or about 17%.

b. To find the probability that 3 or fewer traffic tickets will be issued at the intersection next month, we need to find the cumulative probability up to 3:

P(X ≤ 3) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3)

Using the Poisson distribution formula as before, we get:

P(X ≤ 3) = (e^(-5.4) * 5.4^0) / 0! + (e^(-5.4) * 5.4^1) / 1! + (e^(-5.4) * 5.4^2) / 2! + (e^(-5.4) * 5.4^3) / 3!

P(X ≤ 3) = 0.095 + 0.258 + 0.350 + 0.266 = 0.969

Therefore, the probability that 3 or fewer traffic tickets will be issued at the intersection next month is 0.969 or about 97%.

c. To find the probability that more than 6 traffic tickets will be issued at the intersection next month, we can use the complement rule:

P(X > 6) = 1 - P(X ≤ 6)

We have already calculated P(X ≤ 3) in part b, so we can use the Poisson distribution formula to find P(X = 4), P(X = 5), and P(X = 6) and then add them up:

P(X = 4) = (e^(-5.4) * 5.4^4) / 4! = 0.136
P(X = 5) = (e^(-5.4) * 5.4^5) / 5! = 0.226
P(X = 6) = (e^(-5.4) * 5.4^6) / 6! = 0.237

P(X ≤ 6) = 0.095 + 0.258 + 0.350 + 0.266 + 0.136 + 0.226 + 0.237 = 1

Therefore, P(X > 6) = 1 - 1 = 0

Therefore, the probability that more than 6 traffic tickets will be issued at the intersection next month is 0 or 0%.
User PaoloFCantoni
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