The estimated times (in weeks) and immediate predecessors for the activities in a project are given in the following table. Assume that the activity times are independent. (a) Calculate the expected...
Henry Chow is a stockbroker working for Merrill Lynch. He knows from past experience that there is a 70% chance that his new client will want to include U.S. equity in her portfolio and a 50% chance...
A researcher interviews 50 employees of a large manufacturer and collects data on each workers hourly wage (Wage), years of higher education (EDUC), experience (EXPER), and age (AGE). The entire data...
One study reports that 30% of newly hired MBAs are confronted with unethical business practices during their first year of employment. One business school dean wondered if her MBA graduates had...
A baseball analytics specialist wants to determine which variables are important in predicting a teams wins in a given season. He has collected data related to wins, earned run average (ERA), and...
This frequency distribution represents the commission earned (in dollars) by 100 salespeople employed at several branches of a large chain store. Class limits Frequency 150158 .......5 159167...
A company will be producing the same new product at two different factories, and then the product must be shipped to two warehouses. Factory 1 can send an unlimited amount by rail to warehouse 1...
Nine measurements are taken on the strength of a certain metal. In order, they are 7.2, 8.9, 9.7, 10.5, 10.9, 11.7, 12.9, 13.9, 15.3, and these values correspond to the 10th, 20th, . . . , 90th...
Specifications on a cigar lighter detent are 0.3220 and 0.3200 in. Samples of size 5 are taken every 45 minutes with the results shown in Table 6E.18 (measured as deviations from 0.3210 in 0.0001...
Consider the staffing situation faced by the Gaubert Marketing Company in Problem 6-15. Ignore the salary and part-time information given in part (b) of that problem. Develop a schedule that meets...
Suppose that X has a discrete uniform distribution A random sample of n = 36 is selected from this population. Find the probability that the sample mean is greater than 2.1 but less than 2.5,...
(a) Apply Newtons method to the equation 1/x a = 0 to derive the following reciprocal algorithm: xn+1 = 2xn ax2n (This algorithm enables a computer to find reciprocals without actually dividing.)...
What is Monte Carlo simulation? What principles underlie its use, and what steps are followed in applying it?
In an analysis investigating the usefulness of pennies, the cents portions of 100 randomly selected credit card charges from the author are recorded, and they have a mean of 47.6 cents and a standard...
A gas station with only one gas pump employs the following policy: If a customer has to wait, the price is $3.50 per gallon; if she does not have to wait, the price is $4.00 per gallon. Customers...
Suppose a filling machine is used to fill cartons with a liquid product. The specification that is strictly enforced for the filling machine is 9 1.5 oz. If any carton is produced with weight...
Solve the following LP problem using the corner point graphical method. At the optimal solution, calculate the slack for eachconstraint: Maximize profit = 4X + 4Y subject to
A manufacturer of laundry detergent has introduced a new product that it claims to be more environmentally sound. An extensive survey gives the percentages shown in the table. a. Estimate the...
In a population, = 100 and x = 25. A sample (N = 150) has X = 102. Using two tails of the sampling distribution and the .05 criterion: (a) What is the critical value? (b) Is this sample in the...
Teens were asked in the MTF 2012 survey to report their level of happiness (how are things these days?). The bivariate table includes responses organized by teen's race. Based on an alpha of .05,...
Suppose that X1,X2, . . . is a lognormal geometric random walk with parameters (, 2). More specifically, suppose that Xk = X0exp(r1 + +rk), where X0 is a fixed constant and r1, r2, . . . are...
The curves with equations xn + yn = 1, n = 4, 6, 8, . . . , are called fat circles. Graph the curves with n = 2, 4, 6, 8, and 10 to see why. Set up an integral for the length L2k of the fat circle...
In the December, 1969, American Economic Review (pp. 886896), Nathaniel Leaf reports the following least squares regression results for a cross section study of the effect of age composition on...
In 2009, the New York Yankees won 103 baseball games during the regular season. The table on the next page lists the number of victories (W), the earnedrun average (ERA), and the batting average...
A random sample of size n=100 is taken from a population of size N=3,000 with a population proportion of p=0.34. a. Is it necessary to apply the finite population correction factor? Explain....
The filling variance for boxes of cereal is designed to be .02 or less. A sample of 41 boxes of cereal shows a sample standard deviation of .16 ounces. Use = .05 to determine whether the variance in...
A sociologist assigned to a correctional institution was interested in studying the relationship between intelligence and delinquency. A delinquency index (ranging from 0 to 50) was formulated to...
The soccer team's shirts have arrived in a big box, and people just start grabbing them, looking for the right size. The box contains 4 medium, 10 large, and 6 extra-large shirts. You want a medium...
Suppose the amount of liquid dispensed by a certain machine is uniformly distributed with lower limit A = 8 oz and upper limit B = 10 oz. Describe how you would carry out simulation experiments to...
Use order of h8 Romberg integration to evaluate Compare and t . re' dx
FRED® (Federal Reserve Economic Data), a database of more than 3000 U.S. economic time series, contains historical data on foreign exchange rates. The following data show the foreign exchange...
The fast-food franchiser in Exercise 11.43 was unable to provide enough evidence that the site is acceptable. She is concerned that she may be missing an opportunity to locate the restaurant in a...
A consulting firm submitted a bid for a large research project. The firms management initially felt there was a 50/50 chance of getting the bid. However, the agency to which the bid was submitted...
City Cab, Inc., uses two dispatchers to handle requests for service and to dispatch the cabs. The telephone calls that are made to City Cab use a common telephone number. When both dispatchers are...
A company is about to develop and then market a new product. It wants to build a simulation model for the entire process, and one key uncertain input is the development cost. For each of the...
A media rental store rented the following number of movie titles in each of these categories: 170 horror, 230 drama, 120 mystery, 310 romance, and 150 comedy. If a person selects a movie to rent,...
The coach of an age group swim team needs to assign swimmers to a 200-yard medley relay team to send to the Junior Olympics. Since most of his best swimmers are very fast in more than one stroke, it...
As part of a study of the physiology of wheat maturation, an agronomist selected six wheat plants at random from a field plot. For each plant, she measured the moisture content in two batches of...
A horse-racing fan is contemplating the many different outcomes in an eight-horse race. a. How many different combinations are possible if only the first three places (first, second, and third) are...
PC Magazine provided ratings for several characteristics of computer monitors, including an overall rating (PC Magazine website, April, 2015). The following data show the rating for contrast ratio,...
Use the single-server drive-up bank teller operation referred to in Problems 1 and 2 to determine the following operating characteristics for the system: a. The probability that no customers are in...
The time-series plot in the next column shows the number of new homes built in the Midwest from 2000 to 2009. (a) Describe how this graph is misleading. (b) What is the graph trying to convey? (c) In...
A pharmaceutical manufacturer has come up with a new drug intended to provide greater headache relief than the old formula. Of 250 patients treated with the previous medication, 130 reported fast...
Consider the following frequency table of observations on the random variable X: Values 0 1 2 3 4 Frequency 4 21 10 13 2 (a) Based on these 50 observations, is a binomial distribution with n = 6 and...
Arthur Andersen Enterprise Group/National Small Business United, Washington, conducted a national survey of small-business owners to determine the challenges for growth for their businesses. The top...
The mean and the standard deviation of the sample of 40 trash bag breaking strengths in Table 1.9 are 50.575 and 1.6438, respectively. a. Use the Excel output in Figure to calculate a t-based 95...
Dementia is the loss of the intellectual and social abilities severe enough to interfere with judgment, behavior, and daily functioning. Alzheimer's disease is the most common type of dementia. In...
The managing director of a consulting group has the following to bill to clients: Total Billable $340,000 3,000 $400,000 4,000 $435,000 5,000 $477,000 6,000 $529,000 7,000 $587,000 8,000...
An electronics company produces transistors, resistors, and computer chips. Each transistor requires four units of copper, one unit of zinc, and two units of glass. Each resistor requires three,...
The integer programming problem in the box below has been developed to help First National Bank decide where, out of 10 possible sites, to locate four new branch offices: where Xi represents Winter...
Hockey pucks used by the National Hockey League (NHL) and other professional leagues weigh an average of 163 grams (5.75 ounces). A quality inspector monitors the manufacturing process for hockey...
The use of both alcohol and tobacco by high school seniors has declined in the last 30 years. Alcohol use is down from 68.2 to 43.1%, and the use of cigarettes by high school seniors has decreased...
A research specialist for a large seafood company investigated bacterial growth on oysters and mussels subjected to three different storage temperatures. Nine cold storage units were available. Three...
10-30 Ashcroft Airlines flies a six-passenger commuter fight once a day to Gainesville, Florida. A nonrefundable one-way fare with a reservation costs $129. The daily demand for this flight is given...
A summary of the results is reproduced in the table. Consider the bar graph shown. Identify two ways in which the bar graph might mislead the viewer by overemphasizing the importance of one of the...
The impurity level (in ppm) is routinely measured in an intermediate chemical product. The following data were observed in a recent test: 2.4, 2.5, 1.7, 1.6, 1.9, 2.6, 1.3, 1.9, 2.0, 2.5, 2.6, 2.3,...
As in Exercise 13, from a survey of coworkers you find that 48% of 200 have already received this years flu vaccine. An approximate 95% confidence interval is (0.409, 0.551). a) How would the...
One Friday night, there were 42 carry-out orders at Ashoka Curry Express. (a) Estimate the mean and standard deviation from the sample. (b) Assuming that the data are from a normal distribution, de...
Two television stations compete with each other for viewing audience. Local programming options for the 5:00 p.m. weekday time slot include a sitcom rerun, an early news program, or a home...
Let X denote the number of flaws observed on a large coil of galvanized steel. Seventy-five coils are inspected and the following data were observed for the values of X: Values 1 2 3 4 5 6 7 8...
In a regional spelling bee, the 8 finalists consist of 3 boys and 5 girls. Find the number of sample points in the sample space S for the number of possible orders at the conclusion of the contest...
The acceptance scheme for purchasing lots containing a large number of batteries is to test no more than 75 randomly selected batteries and to reject a lot if a single battery fails. Suppose the...
Use zero- through third-order Taylor series expansions to predict (3) for f (x) = 25x 3 6x 2 + 7x 88 Using a base point at x = 1. Compute the true percent relative error t for each approximation.
Why must the service rate be greater than the arrival rate in a single-channel queuing system?
Based on a study by Dr. P. Sorita Soni at Indiana University, we know that eye colors in the United States are distributed as follows: 40% brown, 35% blue, 12% green, 7% gray, 6% hazel. a. A...
Simple regression was employed to establish the effects of childhood exposure to lead. The effective sample size was about 122 subjects. The independent variable was the level of dentin lead (parts...
An experiment has been conducted for four treatments with eight blocks. Complete the following analysis of variance table. Use α = .05 to test for any significant differences. Source of...
A study of the number of business lunches that executives in the insurance and banking industries claim as deductible expenses per month was based on random samples and yielded the following results:...
A second version of the Markowitz portfolio model maximizes expected return subject to a constraint that the variance of the portfolio must be less than or equal to some specified amount. Consider...
On a laboratory assignment, if the equipment is working, the density function of the observed outcome, X is Find the variance and standard deviation ofX. [2(1 -x), 0
A delivery truck travels from point A to point B and back using the same route each clay there are four traffic lights on the route. Let Xi denote the number of red lights the truck encounters going...
Jackson Hole Manufacturing is a small manufacturer of plastic products used in the automotive and computer industries. One of its major contracts is with a large computer company and involves the...
A decision maker subjectively assigned the following probabilities to the four outcomes of an experiment: P(E1) = .10, P(E2) = .15, P(E3) = .40, and P(E4) = .20. Are these probability assignments...
The following data represent the number of cases of coffee or ï¬lters sold by four sales reps in a recent sales competition. (a) What is the probability that a randomly selected case was...
In Fall 2011, the Wall Street Journal reported that 44% of smartphone purchases made by people with incomes between $35,000 to $50,000 were Android phones.16 (a) If the story is based on a sample of...
A manufacturer of cat food is planning to survey households in the United States to determine purchasing habits of cat owners. Among the variables to be collected are the following: i. The primary...
A simple random sample of 300 items is selected from a large shipment, and testing reveals that 4% of the sampled items are defective. The supplier claims that no more than 2% of the items in the...
Consider the assignment problem having the following cost table. (a) Draw the network representation of this assignment problem. (b) Formulate this problem as a transportation problem by constructing...
Let CP denote carcinogenic potential, TR test results, and FR field results. Suppose that for Figure 7.23 we have the following probabilities: Figure 7.23 PiCP High) = 0.27 PiTR Positive CP...
Consider the following set of constraints: X1 + 2x2 + 2x3 + 4x4 40 2x1 - x2 + x3 + 2x4 8 4x1 + 2x2 + x3 - x4 10 X1, x2, x3, x4 0 Solve the problem for each of the following objective functions....
SPSS will calculate standard scores for any distribution. Examine the distribution of EDUC (years of school completed). a. Have SPSS calculate Z scores for EDUC. (See the SPSS Demonstration above if...
In a study comparing banks in Germany and Great Britain, a sample of 145 matched pairs of banks was formed. Each pair contained one bank from Germany and one from Great Britain. The pairings were...
Control charts for with n = 4 are maintained on a quality characteristic. The parameters of these charts are as follows and x s Both charts exhibit control. Specifications on the quality...
Consider the two processes shown in Table 8E.1 (the sample size n = 5). Specifications are at 100 ± 10. Calculate Cp, Cpk, and Cpm and interpret these ratios. Which process would you prefer to...
Will improving customer service result in higher stock prices for the companies providing the better service? When a companys satisfaction score has improved over the prior years results and is above...
In an article in the Journal of Advertising, Weinberger and Spotts compare the use of humor in television ads in the United States and in the United Kingdom. Suppose that independent random samples...
Reboot, Inc. is a manufacturer of hiking boots. Demand for boots is highly seasonal. In particular, the demand in the next year is expected to be 3,000, 4,000, 8,000, and 7,000 pairs of boots in...
Hospitals typically require backup generators to provide electricity in the event of a power outage. Assume that emergency backup generators fail 22% of the times when they are needed (based on data...
A biotechnology company produces a therapeutic drug whose concentration has a standard deviation of 4 grams per liter. A new method of producing this drug has been proposed, although some additional...
A metal storage tank with volume V is to be constructed in the shape of a right circular cylinder surmounted by a hemisphere. What dimensions will require the least amount of metal?
Determine whether the two random variables of Exercise 3.49 are dependent or independent.
Determine the real root of x3.5 = 80: (a) Analytically, and (b) With the false-position method to within s = 2.5 %. Use initial guesses of 2.0 and 5.0
The Costello Music Company has been in business for five years. During that time, the sales of electric organs have grown from 12 units in the first year to 76 units in the most recent year. Fred...
A data set contains the following seven values. 6 2 4 9 1 3 5 a. Find the range. b. Find the mean absolute deviation. c. Find the population variance. d. Find the population standard deviation. e....
Data envelopment analysis can measure the relative efficiency of a group of hospitals. The following data from a particular study involving seven teaching hospitals include three input measures and...
Time- depth recorders were deployed on 6 of the 76 captured turtles. The time-depth recorders allowed the environmentalists to track the movement of the sea turtles in the lagoon. These 6 turtles had...
A company sends a random sample of 16 of its salespeople to a course designed to increase their motivation and, hence, presumably their effectiveness. In the following year these people generated...
Rosenberg Land Development (RLD) is a developer of condominium properties in the Southwest United States. RLD has recently acquired a 40.625 acre site outside of Phoenix, Arizona. Zoning restrictions...
Assume that the length of a typical televised baseball game, including all the commercial timeouts, is normally distributed with mean 2.45 hours and standard deviation 0.37 hour. Consider a televised...
Calculate the following quantities using Excel. a. P(-2.00 t10 1.00), where t10 has a t distribution with 10 degrees of freedom. b. P(-2.00 t100 1.00), where t100 has a t distribution with 100...