Consider writing onto a computer disk and then sending it through a certifier that counts the number of missing pulses. Suppose this number x has a Poisson distribution with parameter μ = 0.5. (Round your answers to three decimal places.)
(a) What is the probability that a disk has exactly one missing pulse?
(b) What is the probability that a disk has at least two missing pulses?
(c) lf two disks are independently selected, what is the probability that neither contains a missing pulse?

Respuesta :

Answer:

Explained below.

Step-by-step explanation:

The random variable X is defined as the number of missing pulses and follows a Poisson distribution with parameter (μ = 0.50).

The probability mass function of X is as follows:

[tex]P(X=x)=\frac{e^{-\mu}\ \mu^{x}}{x!};\ x=0,1,2,3...[/tex]

(a)

Compute the probability that a disk has exactly one missing pulse as follows:

[tex]P(X=1)=\frac{e^{-0.50}\ 0.50^{1}}{1!}=0.3033[/tex]

Thus, the probability that a disk has exactly one missing pulse is 0.3033.

(b)

Compute the probability that a disk has at least two missing pulses as follows:

[tex]P(X\geq 2)=1-P(X<2)\\[/tex]

                [tex]=1-[P(X=0)+P(X=1)]\\=1-[\frac{e^{-0.50}\ 0.50^{0}}{0!}+\frac{e^{-0.50}\ 0.50^{1}}{1!}]\\=1-0.6065-0.3033\\=0.0902[/tex]

Thus, the probability that a disk has at least two missing pulses is 0.0902.

(c)

It is provided that the two disks selected are independent of each other.

The probability that a disk has no missing pulses is:

[tex]P(X=0)=\frac{e^{-0.50}\ 0.50^{0}}{0!}=0.6065[/tex]

Compute the probability that neither of the two disks contains a missing pulse as follows:

[tex]P(X_{1}=0,\ X_{2}=0)=P(X_{1}=0)\times P(X_{2}=0)[/tex]

                               [tex]=0.6065\times 0.6065\\=0.367842\\\approx 0.3678[/tex]

Thus, the probability that neither of the two disks contains a missing pulse is 0.3678.