Exam 5: Discrete Probability Distributions

A lab orders 100 rats a week for each of the 52 weeks in the year for experiments that the lab conducts.Prices for 100 rats follow the following distribution: How much should the lab budget for next year's rat orders be,assuming this distribution does not change?

SCENARIO 5-6 The quality control manager of Green Bulbs Inc.is inspecting a batch of energy saving compact fluorescent light bulbs.When the production process is in control,the mean number of bad bulbs per shift is 6.0. -Referring to Scenario 5-6,what is the probability that any shift being inspected has produced fewer than 5.0 bad bulbs.

SCENARIO 5-8 Two different designs on a new line of winter jackets for the coming winter are available for your manufacturing plants.Your profit (in thousands of dollars)will depend on the taste of the consumers when winter arrives.The probability of the three possible different tastes of the consumers and the corresponding profits are presented in the following table. -Referring to Scenario 5-8,if your investment preference is to minimize the amount of risk that you must take and do not care at all about the expected profit,will you choose a production mix that will consist of 10%,30%,50%,70%,or 90% of your production lines for Design A and the remaining for Design B?

The connotation "expected value" or "expected gain" from playing roulette at a casino means

SCENARIO 5-3 The following table contains the probability distribution for X = the number of retransmissions necessary to successfully transmit a 1024K data package through a network. -Referring to Scenario 5-3,the mean or expected value for the number of retransmissions is_____.

SCENARIO 5-10 An accounting firm in a college town usually recruits employees from two of the universities in town.This year,there are fifteen graduates from University A and five from University B and the firm decides to hire six new employees from the two universities. -Referring to Scenario 5-10,what is the probability that all six of the new employees will be from University A?

A multiple-choice test has 30 questions.There are 4 choices for each question.A student who has not studied for the test decides to answer all questions randomly.What type of probability distribution can be used to figure out his chance of getting at least 20 questions right?

The number of 911 calls in a small city has a Poisson distribution with a mean of 10 calls a day.The probability of 2 or more 911 calls in a day is _____.

SCENARIO 5-13 Bell Computers manufactures personal computers at two plants,one in Arkansas and one in Utah.The Arkansas plant has 50 employees;the Utah one has 40 employees.A random sample of 12 employees was selected to complete a job satisfaction questionnaire -Using Scenario 5-13,what is the probability exactly three of the employees completing the questionnaire are from the Utah plant?

Suppose that history shows that 60% of college students prefer Brand C cola.A sample of 5 students is to be selected.The probability that at least 1 prefers brand C is _____.

SCENARIO 5-12 Phone calls arrive at the rate of 50 per hour at the reservation desk for Queen City Airways.The desk manager has asked you for an analysis of the call rates and probabilities to better understand the operation and determine if more call desk workers are needed. -Using Scenario 5-12,What is the expected number of calls when calculating the probability of receiving three calls in a 6-minute period?

SCENARIO 5-7 There are two houses with almost identical characteristics available for investment in two different neighborhoods with drastically different demographic composition.The anticipated gain in value when the houses are sold in 10 years has the following probability distribution: -Referring to Scenario 5-7,if your investment preference is to minimize the amount of risk that you must take and do not care at all about the expected return,will you choose a portfolio that will consist of 10%,30%,50%,70%,or 90% of your money on the house in neighborhood A and the remaining on the house in neighborhood B?

SCENARIO 5-8 Two different designs on a new line of winter jackets for the coming winter are available for your manufacturing plants.Your profit (in thousands of dollars)will depend on the taste of the consumers when winter arrives.The probability of the three possible different tastes of the consumers and the corresponding profits are presented in the following table. -Referring to Scenario 5-8,if you decide to choose Design A for 90% of the production lines and Design B for the remaining production lines,what is the coefficient of variation of your investment?

SCENARIO 5-6 The quality control manager of Green Bulbs Inc.is inspecting a batch of energy saving compact fluorescent light bulbs.When the production process is in control,the mean number of bad bulbs per shift is 6.0. -Referring to Scenario 5-6,what is the probability that any shift being inspected has produced 4.0 bad bulbs.

SCENARIO 5-7 There are two houses with almost identical characteristics available for investment in two different neighborhoods with drastically different demographic composition.The anticipated gain in value when the houses are sold in 10 years has the following probability distribution: -Referring to Scenario 5-7,if you can invest 30% of your money on the house in neighborhood A and the remaining on the house in neighborhood B,what is the portfolio expected return of your investment?

A company has 125 personal computers.The probability that any one of them will require repair on a given day is 0.025.To find the probability that exactly 20 of the computers will require repair on a given day,one will use what type of probability distribution?

SCENARIO 5-8 Two different designs on a new line of winter jackets for the coming winter are available for your manufacturing plants.Your profit (in thousands of dollars)will depend on the taste of the consumers when winter arrives.The probability of the three possible different tastes of the consumers and the corresponding profits are presented in the following table. -Referring to Scenario 5-8,if you decide to choose Design A for 10% of the production lines and Design B for the remaining production lines,what is the coefficient of variation of your investment?

SCENARIO 5-13 Bell Computers manufactures personal computers at two plants,one in Arkansas and one in Utah.The Arkansas plant has 50 employees;the Utah one has 40 employees.A random sample of 12 employees was selected to complete a job satisfaction questionnaire -Using Scenario 5-13,what is the probability at least three of the employees completing the questionnaire are from the Arkansas plant?

A professor receives,on average,24.7 e-mails from students the day before the midterm exam.To compute the probability of receiving at least 10 e-mails on such a day,he will use what type of probability distribution?

SCENARIO 5-5 From an inventory of 48 new cars being shipped to local dealerships,corporate reports indicate that 12 have defective radios installed. -Referring to Scenario 5-5,what is the probability out of the 8 new cars it just received that,when each is tested,exactly half of the cars have defective radios?