Exam 6: Random Variables and Probability Models

For quality control purposes, a company that manufactures sim chips for cell/smart phones routinely takes samples from its production process. Since it is important that These chips are nearly fault free, one inspection check involves using microscopic Equipment to count the number of imperfections on each chip. Suppose the average Number of imperfections per 1000 sim chips is 3. What is the probability that a sample of1000 sim chips has 2 imperfections?

It is estimated that 20% of luxury cars manufactured in 2012 were silver. A car dealership typically sells 20 luxury cars per month. The probability that more than 10 of The luxury cars sold per month are silver is

A small business just leased a new presentation equipment and a color laser printer for three years. The service contract for the computer offers unlimited repairs for a fee of $100 a year plus a $25 service charge for each repair needed. The company's research indicates that during a given year 86% of these computers need no repairs, 9% need to be repaired once, 4% twice, 1% three times, and none required more than three repairs. A. Find the expected number of repairs for this kind of computer per year. b. Find the standard deviation of the number of repairs per year. c. What are the mean and standard deviation of the company's annual expense with the service contract for the computer?

A fast food restaurant just leased a new freezer and food fryer for three years. The service contract for the freezer offers unlimited repairs for a fee of $125 a year plus a $35 service charge for each repair needed. The restaurant's research indicates that during a given year 80% of these freezers need no repairs, 11% needed to be serviced once, 5% twice, 4% three times, and none required more than three repairs. A. Find the expected number of repairs for this freezer per year. b. Find the standard deviation of the number of repairs per year. c. What are the mean and standard deviation of the restaurant's annual expense with the service contract for the freezer?

Internet service providers (ISP) need to resolve customer problems as quickly as possible. For one ISP, past data indicates that the likelihood is .80 that customer calls Regarding Internet service interruptions are resolved within one hour. Out of the next 10 Customer calls about interrupted service, the probability that exactly 7 will be resolved Within one hour is

For quality control purposes, a company that manufactures sim chips for cell/smart phones routinely takes samples from its production process. Since it is important that these chips are nearly fault free, one inspection check involves using microscopic equipment to count the number of imperfections on each chip. Suppose the average number of imperfections per 1000 sim chips is 3. A. What is the probability that a sheet of this size has 2 imperfections? b. What is the probability that a sheet of this size has no more than 2 imperfections? c. What is the probability that a sheet half this size (18 sq. ft.) has 2 imperfections?

A fast food restaurant just leased a new freezer and food fryer for three years. The service contract for the freezer offers unlimited repairs for a fee of $125 a year plus a $35 Service charge for each repair needed. The restaurant's research indicates that during a Given year 80% of these freezers need no repairs, 11% needed to be serviced once, 5% Twice, 4% three times, and none required more than three repairs. The standard deviation Of the number of repairs for this freezer per year is

It is estimated that 20% of luxury cars manufactured in 2012 were silver. A car dealership typically sells 20 luxury cars per month. The probability that 8 of the luxury Cars sold per month are silver is