The number x of people entering the intensive care unit at a particular hospital on any one day has a Poisson probability distribution with mean equal to four persons per day. (a) What is the probability that the number of people entering the intensive care unit on a particular day is two? (Round your answer to three decimal places.) What is the probability that the number of people entering the intensive care unit on a particular day is less than or equal to two? (Round your answer to three decimal places.) (b) Is it likely that, on a given day, the number of people entering the intensive care unit, will exceed an x-value of 8? Calculate the mean and standard deviation of the probability distribution to explain your answer. O Yes it is likely because x is less than 2 standard deviations above the mean. O No it is not likely because x is more than 2 standard deviations above the mean.
(a) The number of people entering the intensive care unit on a particular day follows a Poisson distribution with a mean (λ) equal to four persons per day. To calculate the probability:
Probability that x = 2:
P(x = 2) = (e^(-λ) * λ^x) / x!
P(x = 2) = (e^(-4) * 4^2) / 2!
P(x = 2) ≈ (0.01832 * 16) / 2 ≈ 0.1832 (rounded to three decimal places).
Probability that x ≤ 2:
P(x ≤ 2) = P(x = 0) + P(x = 1) + P(x = 2)
To calculate P(x = 0):
P(x = 0) = (e^(-λ) * λ^0) / 0!
P(x = 0) = (e^(-4) * 1) / 1 = 0.01832 (rounded to three decimal places).
To calculate P(x = 1):
P(x = 1) = (e^(-λ) * λ^1) / 1!
P(x = 1) = (e^(-4) * 4) / 1 = 0.1465 (rounded to three decimal places).
Now, add these probabilities:
P(x ≤ 2) = 0.01832 + 0.1465 + 0.1832 ≈ 0.348 (rounded to three decimal places)
Step by step
Solved in 3 steps