Let X = the time between two successive arrivals at the drive-up window of a local bank. If X has an exponential distribution with λ = 1, (which is identical to a standard gamma distribution with α = 1), compute the following. (If necessary, round your answer to three decimal places.) (a) The expected time between two successive arrivals 1 Correct: Your answer is correct. (b) The standard deviation of the time between successive arrivals

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Answer:

(a) The expected time between two successive arrivals is 1.000.

(b) The standard deviation of the time between successive arrivals is 1.000.

Step-by-step explanation:

The random variable X is defined as the time between two successive arrivals at the drive-up window of a local bank.

The random variable X follows an Exponential distribution with parameter λ = 1.

(a)

The mean or expected value of an Exponential distribution is:

[tex]\mu=E(X)=\frac{1}{\lambda}[/tex]

Compute the mean value of X as follows:

[tex]\mu=E(X)=\frac{1}{\lambda}\\\mu=\frac{1}{1}\\\mu=1[/tex]

Thus, the expected time between two successive arrivals is 1.000.

(b)

The standard deviation of an Exponential distribution is:

[tex]\sigma=\sqrt{\frac{1}{\lambda^{2}}}[/tex]

Compute the standard deviation of X as follows:

[tex]\sigma=\sqrt{\frac{1}{\lambda^{2}}}=\sqrt{\frac{1}{1^{2}}}=1[/tex]

Thus, the standard deviation of the time between successive arrivals is 1.000.