Data collected by emergency responders in a large city suggest that on averagethere are 6.9 drug overdoses per night.(a) What is the probability that there are 3 drug overdoses in a random night(please round to 3 decimal places)?(b) What is the probability that there are at most 3 drug overdoses in a randomnight (please round to 3 decimal places)?Quartion HelpMessage instructor

Respuesta :

Answer

a) Probability that there are 3 drug overdoses in a random night = 0.055

b) Probability that there are at most 3 drug overdoses in a random

night = 0.087

Explanation

The Poisson distribution will be used to solve this one.

The Poisson distribution is given as

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

where

x = actual variable whose probability we want to find = 3 drug overdoses in one night

μ = mean of the distribution = 6.9 drug overdoses per night

[tex]\begin{gathered} P(X=x)=\frac{(e^{-\mu})(\mu^x)}{x!} \\ P(X=3)=\frac{(e^{-6.9})(6.9^3)}{3!}=0.055 \end{gathered}[/tex]

b) For the probability of at most 3 drug overdoses in one night,

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

For each of them,

μ = 6.9

But for x, we will calculate for each of them using

x = 0, x = 1, x = 2, x = 3

[tex]\begin{gathered} P(X=x)=\frac{(e^{-\mu})(\mu^x)}{x!} \\ P(X=0)=\frac{(e^{-6.9})(6.9^0)}{0!}=0.00101 \\ P(X=1)=\frac{(e^{-6.9})(6.9^1)}{1!}=0.00695 \\ P(X=2)=\frac{(e^{-6.9})(6.9^2)}{2!}=0.02399 \\ P(X=3)=\frac{(e^{-6.9})(6.9^3)}{3!}=0.0552 \end{gathered}[/tex]

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

P (X ≤ 3) = 0.00101 + 0.00695 + 0.02399 + 0.0552 = 0.08714 = 0.087

Hope this Helps!!!