Questions from Business Statistics

Q: According to the ICAO, the average operating cost of an A320

According to the ICAO, the average operating cost of an A320 jet airliner is $2,270 per hour. Suppose the operating costs of an A320 jet airliner are normally distributed with a standard deviation of...

Q: Supermarkets usually become busy at about 5 P.M. on

Supermarkets usually become busy at about 5 P.M. on weekdays because many workers stop by on the way home to shop. Suppose at that time arrivals at a supermarket’s express checkout station are Poisson...

Q: In a recent year, the average daily circulation of the Wall

In a recent year, the average daily circulation of the Wall Street Journal was 2,276,207. Suppose the standard deviation is 70,940. Assume the paper’s daily circulation is normally distributed. On wha...

Q: The Wall Street Journal reported some interesting statistics on the job market

The Wall Street Journal reported some interesting statistics on the job market. One statistic is that 40% of all workers say they would change jobs for “slightly higher pay.” In addition, 88% of compa...

Q: Determine the probabilities for the following normal distribution problems. a

Determine the probabilities for the following normal distribution problems. a) μ = 604, σ = 56.8, x ≤ 635 b) μ = 48, σ = 12, x < 20 c) μ = 111, σ = 33.8, 100 ≤ x < 150 d) μ = 264, σ = 10.9, 250 < x <...

Q: Incoming phone calls generally are thought to be Poisson distributed. If

Incoming phone calls generally are thought to be Poisson distributed. If an operator averages 2.2 phone calls every 30 seconds, what is the expected (average) amount of time between calls? What is the...

Q: Shown here is a Minitab output. Suppose the data represent the

Shown here is a Minitab output. Suppose the data represent the number of sales associates who are working in a department store on any given retail day. Describe the distribution including the mean an...

Q: A manufacturing company produces a metal rod. Use the Excel output

A manufacturing company produces a metal rod. Use the Excel output shown here to describe the weight of the rod. Interpret the probability values in terms of the manufacturing process. Normal Distribu...

Q: Suppose the Minitab output shown here represents the analysis of the length

Suppose the Minitab output shown here represents the analysis of the length of home-use cell phone calls in terms of minutes. Describe the distribution of cell phone call lengths and interpret the mea...

Q: Tompkins Associates reports that the mean clear height for a Class A

Tompkins Associates reports that the mean clear height for a Class A warehouse in the United States is 22 feet. Suppose clear heights are normally distributed and that the standard deviation is 4 feet...