In a 40-year period, a city's official weather station recorded 78 snowstorms with at least 12 inches of total snow accumulation. Assume that this pattern follows a Poisson distribution. Find the probability that the city's weather station records exactly 4 snowstorms with at least 12 inches of total snow accumulation for one randomly selected year in the period. Use Excel to find the probability.

Respuesta :

Answer:

11.18% probability that the city's weather station records exactly 4 snowstorms with at least 12 inches of total snow accumulation for one randomly selected year in the period.

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 time interval.

78 snowstorms with at least 12 inches of total snow accumulation.

This means that [tex]\mu = \frac{78}{12} = 6.5[/tex]

Find the probability that the city's weather station records exactly 4 snowstorms with at least 12 inches of total snow accumulation for one randomly selected year in the period.

This is P(X = 4). So

[tex]P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}[/tex]

[tex]P(X = 4) = \frac{e^{-6.5}*(6.5)^{4}}{(4)!} = 0.1118[/tex]

11.18% probability that the city's weather station records exactly 4 snowstorms with at least 12 inches of total snow accumulation for one randomly selected year in the period.