The number of large cracks in a length of pavement along a certain street has a Poisson distribution with a mean of 1 crack per 100 ft. a. What is the probability that there will be exactly 8 cracks in a 500 ft length of pavement

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Answer:

6.53% probability that there will be exactly 8 cracks in a 500 ft length of pavement

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

e = 2.71828 is the Euler number

[tex]\mu[/tex] is the mean in the given interval.

Poisson distribution with a mean of 1 crack per 100 ft.

So [tex]\mu = \frac{ft}{100}[/tex], in which ft is the length of the pavement.

What is the probability that there will be exactly 8 cracks in a 500 ft length of pavement

500ft, so [tex]\mu = \frac{500}{100} = 5[/tex]

This is P(X = 8).

[tex]P(X = 8) = \frac{e^{-5}*5^{8}}{(8)!} = 0.0653[/tex]

6.53% probability that there will be exactly 8 cracks in a 500 ft length of pavement