Exam 7: B: Random Variables and Discrete Probability Distributions

The number of customers arriving at a department store in a 5-minute period has a Poisson distribution.

Post office The number of arrivals at a local post office between 3:00 and 5:00 P.M.has a Poisson distribution with a mean of 12. -{{Post Office Narrative} Find the probability that the number of arrivals between 4:00 and 5:00 P.M.is exactly two.

In a Poisson distribution,the mean and variance are equal.

In a Poisson distribution,the:

Unsafe Levels of Radioactivity The number of incidents at a nuclear power plant has a Poisson distribution with a mean of 6 incidents per year. -{Unsafe Levels of Radioactivity Narrative} Find the probability that there will be exactly 3 incidents in a year.

Post office The number of arrivals at a local post office between 3:00 and 5:00 P.M.has a Poisson distribution with a mean of 12. -{Post Office Narrative} Find the probability that the number of arrivals between 3:30 and 4:00 P.M.is at least 10.

In a Poisson experiment,the probability of a success in an interval is ____________________ to the size of the interval.

The largest value that a Poisson random variable X can have is n.

In a Poisson distribution,the variance and standard deviation are equal.

The Poisson distribution is applied to events for which the probability of occurrence over a given span of time,space,or distance is very small.

Classified Department Phone Calls A classified department receives an average of 10 telephone calls each afternoon between 2 and 4 P.M.The calls occur randomly and independently of one another. -{Classified Department Phone Calls Narrative} Find the probability that the department will receive seven calls between 2 and 3 P.M.on a particular afternoon.

In a(n)____________________ experiment,the probability of a success in an interval is the same for all equal-sized intervals.

Classified Department Phone Calls A classified department receives an average of 10 telephone calls each afternoon between 2 and 4 P.M.The calls occur randomly and independently of one another. -{Classified Department Phone Calls Narrative} Find the probability that the department will receive at least five calls between 2 and 4 P.M.on a particular afternoon.

911 Phone Calls 911 phone calls arrive at the rate of 30 per hour at the local call center. -{911 Phone Calls Narrative} If no calls are currently being processed,what is the probability that the desk employee can take four minutes break without being interrupted?

In Poisson experiment,the probability of more than one success in an interval approaches ____________________ as the interval becomes smaller.

A Poisson random variable is the number of successes that occur in a period of ____________________ or an interval of ____________________ in a Poisson experiment.

Classified Department Phone Calls A classified department receives an average of 10 telephone calls each afternoon between 2 and 4 P.M.The calls occur randomly and independently of one another. -{Classified Department Phone Calls Narrative} Find the probability that the department will receive 13 calls between 2 and 4 P.M.on a particular afternoon.

The Poisson random variable is a:

The Poisson random variable is a discrete random variable with infinitely many possible values.

The number of customers making a purchase out of 30 randomly selected customers has a Poisson distribution.