Consider the following project network. Note that the normal or expected activity times are denoted Ïi, I = A, B, . . . , I. Let xi = the earliest finish time for activity i. Formulate a linear...
The Ethan Allen tour boat capsized and sank in Lake George, New York, and 20 of the 47 passengers drowned. Based on a 1960 assumption of a mean weight of 140 lb for passengers, the boat was rated to...
The length of an injection-molded plastic case that holds magnetic tape is normally distributed with a length of 90.2 millimeters and a standard deviation of 0.1 millimeter. (a) What is the...
A book publisher monitors the size of shipments of its textbooks to university bookstores. For a sample of texts used at various schools, the 95% confidence interval for the size of the shipment was...
The state of California has a mean annual rainfall of 22 inches, whereas the state of New York has a mean annual rainfall of 42 inches (Current Results website, October 27, 2012). Assume that the...
Jobco is planning to produce at least 2000 widgets on three machines. The minimum lot size on any machine is 500 widgets. The following table gives the pertinent data of the situation. Formulate the...
A survey conducted by the Northwestern University Lindquist-Endicott Report asked 320 companies about the procedures they use in hiring. Only 54% of the responding companies review the applicants...
According to the Digest of Educational Statistics, a certain group of preschool children under the age of one year each spends an average of 30.9 hours per week in nonparental care. A study of state...
Advertising expenses are a significant component of the cost of goods sold. Listed below is a frequency distribution showing the advertising expenditures for 60 manufacturing companies located in the...
The payouts for the Powerball lottery and their corresponding odds and probabilities of occurrence are shown below. The price of a ticket is $1.00. Find the mean and standard deviation of the payout....
In a USA Today poll of 737 respondents, 92% said that they do not open unfamiliar e-mail and instant-message links. Use a 0.01 significance level to test the claim that more than 75% of us do not...
The following table shows the percentage of individuals in each age group who use an online tax program to prepare their federal income tax return (CompleteTax website, November 9, 2012). Online Tax...
The smallest defect in a computer chip will render the entire chip worthless. Therefore, tight quality control measures must be established to monitor the chips. In the past, the percentage defective...
In preparing for the upcoming holiday season, Fresh Toy Company (FTC) designed a new doll called The Dougie that teaches children how to dance. The fixed cost to produce the doll is $100,000. The...
The prior probabilities for events A1, A2, and A3 are P(A1) = 0.20, P(A2) = 0.50, and P(A3) = 0.30. The conditional probabilities of event B given A1, A2, and A3 are P(B | A1) = 0.50, P(B | A2) =...
The management of Madeira Manufacturing Company is considering the introduction of a new product. The fixed cost to begin the production of the product is $30,000. The variable cost for the product...
The NCAA estimates that the yearly value of a full athletic scholarship at in-state public universities is $19,000 (The Wall Street Journal, March 12, 2012). Assume the scholarship value is normally...
Guest ages at a Vail Resorts ski mountain typically have a right-skewed distribution. Assume the standard deviation () of age is 14.5 years. (a) Even though the population distribution of age is -...
Computer keyboard failures are due to faulty electrical connects (12%) or mechanical defects (88%). Mechanical defects are related to loose keys (27%) or improper assembly (73%). Electrical connect...
Use the following set of pressure-volume data to find the best possible virial constants (A1 and A2) for the equation of state shown below. R = 82.05 ml atm/gmol K and T = 303K. PV RT =I+ 1.108 1.363...
GloFish, Inc. has genetically engineered a species of fish that glows in normal lighting conditions. The company believes the new fish will be a huge success as a new pet option for children and...
Scrapper Elevator Company has 20 sales representatives who sell its product throughout the United States and Canada. The number of units sold last month by each representative is listed below. Assume...
A backgammon player will be playing three consecutive matches with friends tonight. For each match, he will have the opportunity to place an even bet that he will win; the amount bet can be any...
The article "Expectation Analysis of the Probability of Failure for Water Supply Pipes" (J. of Pipeline Systems Engr. and Practice, May 2012: 36-46) proposed using the Poisson distribution to model...
A golfer keeps track of his score for playing nine holes of golf (half a normal golf round). His mean score is 85 with a standard deviation of 11. Assuming that the second 9 has the same mean and...
An airport limousine can accommodate up to four passengers on any one trip. The company will accept a maximum of six reservations for a trip, and a passenger must have a reservation. From previous...
Fifty pro-football rookies were rated on a scale of 1 to 5, based on performance at a training camp as well as on past performance. A ranking of 1 indicated a poor prospect whereas a ranking of 5...
In archaeology, the depth (below surface grade) at which artifacts are found is very important. Greater depths sometimes indicate older artifacts, perhaps from a different archaeological period....
In a survey conducted by TheKnot.com, 1165 engaged or married women were asked about the importance of a bended knee when making a marriage proposal. Among the 1165 respondents, 48% said that the...
(a) A type of lightbulb is labeled as having an average lifetime of 1000 hours. Its reasonable to model the probability of failure of these bulbs by an exponential density function with mean = 1000....
The Pelnor Corporation is the nation's largest manufacturer of industrial-size washing machines. A main ingredient in the production process is 8- by 10-foot sheets of stainless steel. The steel is...
In a recent poll, the Gallup Organization found that 45% of adult Americans believe that the overall state of moral values in the United States is poor. Suppose a survey of a random sample of 25...
Education influences attitude and lifestyle. Differences in education are a big factor in the generation gap. Is the younger generation really better educated? Large surveys of people age 65 and...
The Roniger Company produces two products: bed mattresses and box springs. A prior contract requires that the firm produce at least 30 mattresses or box springs, in any combination. In addition,...
When set at the standard position, Autopitch can throw hard balls toward a batter at an average speed of 60 mph. Autopitch devices are made for both major- and minor-league teams to help them improve...
Based on a Harris poll, among adults who regret getting tattoos, 20% say that they were too young when they got their tattoos. Assume that five adults who regret getting tattoos are randomly...
Gamma Corporation is considering the installation of governors on cars driven by its sales staff. These devices would limit the car speeds to a preset level, which is expected to improve fuel...
A car rental agency at a local airport has available 5 Fords, 7 Chevrolets, 4 Dodges, 3 Hondas, and 4 Toyotas. If the agency randomly selects 9 of these cars to chauffeur delegates from the airport...
The price drivers pay for gasoline often varies a great deal across regions throughout the United States. The following data show the price per gallon for regular gasoline for a random sample of...
The Wall Street Journal reported that Walmart Stores Inc. is planning to lay off 2300 employees at its Sam's Club warehouse unit. Approximately half of the layoffs will be hourly employees (The Wall...
The Battery Park Stable feeds and houses the horses used to pull tourist-filled carriages through the streets of Charleston's historic waterfront area. The stable owner, an ex-racehorse trainer,...
Use the values in the cross-tabulation table to solve the equations given. a. P(A D) = ______ b. P(E B) = ______ c. P(D E) = ______ d. P(C F) =______ D EF A 5812 B|10|614 C825
Listed below are skull breadths obtained from skulls of Egyptian males from three different epochs. Use a 0.05 significance level to test the claim that the samples are from populations with the same...
A sample containing years to maturity and yield for 40 corporate bonds is contained in the data file named CorporateBonds (Barrons, April 2, 2012). a. What is the sample mean years to maturity for...
The next diagram depicts a system of aqueducts that originate at three rivers (nodes R1, R2, and R3) and terminate at a major city (node T), where the other nodes are junction points in the system....
Ohio Logistics manages the logistical activities for firms by matching companies that need products shipped with carriers that can provide the best rates and best service for the companies. Ohio...
According to a 2013 study by the Pew Research Center, 15% of adults in the United States do not use the Internet (Pew research Center website, December, 15, 2014). Suppose that 10 adults in the...
Suppose that (Yi, Xi) satisfy the assumptions in Key Concept 4.3. A random sample of size n = 250 is drawn and yields = 5.4 + 3.2X, R2 = 0.26, SER = 6.2. (3.1) (1.5) (a) Test H0: i = 0 vs. H1: 1 0...
Movies Tonight is a typical video and DVD movie rental outlet for home-viewing customers. During the weeknight evenings, customers arrive at Movies Tonight with an arrival rate of 1.25 customers per...
A shortage of candidates has required school districts to pay higher salaries and offer extras to attract and retain school district superintendents. The following data show the annual base salary...
Data Set 1 in Appendix B includes 40 pulse rates of men, and those pulse rates have a mean of 67.3 beats per minute and a standard deviation of 10.3 beats per minute. That data set also includes 40...
A bearing used in an automotive application is suppose to have a nominal inside diameter of 1.5 inches. A random sample of 25 bearings is selected and the average inside diameter of these bearings is...
In Problems 5-15 and 5-16, three different forecasts were developed for the demand for fertilizer. These three forecasts are a 3-year moving average, a weighted moving average, and a trend line....
In the manufacturing of a chemical adhesive, 3% of all batches have raw materials from two different lots. This occurs when holding tanks are replenished and the remaining portion of a lot is...
A real estate development firm, Peterson and Johnson, is considering five possible development projects. The following table shows the estimated long-run profit ( net present value ) that each...
The Boston Fire Department receives 911 calls at a mean rate of 1.6 calls per hour (Mass.gov website, November 2012). Suppose the number of calls per hour follows a Poisson probability distribution....
Powerball is a multistate lottery. The following probability distribution represents the cash prizes of Powerball with their corresponding probabilities. x (cash prize, $) ...........P(x) Grand prize...
(a) A random sample of size 144 is taken from the local population of grade- school children. Each child estimates the number of hours per week spent watching TV. At this point, what can be said...
The Premiere Bank soon will be hooking up computer terminals at each of its branch offices to the computer at its main office using special phone lines with telecommunications devices. The phone line...
Weighing trucks One kind of scale for weighing trucks can measure their weight as they drive across a plate. Is this method consistent with the traditional method of static weighing? Are the...
Allegiant Airlines charges a mean base fare of $89. In addition, the airline charges for making a reservation on its website, checking bags, and in-flight beverages. These additional charges average...
As reported in Runners World magazine, the times of the finishers in the New York City 10-km run are normally distributed with mean 61 minutes and standard deviation 9 minutes. Let x denote finishing...
Two different formulations of an oxygenated motor fuel are being tested to study their road octane numbers. The variance of road octane number for formulation 1 is = 1.5, and for formulation 2 it is...
The food services division of Cedar River Amusement Park Inc. is studying the amount that families who visit the amusement park spend per day on food and drink. A sample of 40 families who visited...
Suppose that 60% of the students do homework regularly. It is also known that 80% of students, who had been doing homework regularly, end up doing well in the course (get a grade of A or B). Only 20%...
Using the alternative-parameter method, determine the parameters of the following distributions based on the given assessments. Refer to Step 5.5 if necessary. a. Find the parameter value for the...
All airplane passengers at the Lake City Regional Airport must pass through a security screening area before proceeding to the boarding area. The airport has three screening stations available, and...
The Wall Street Journal reported that the age at first startup for 55% of entrepreneurs was 29 years of age or less and the age at first startup for 45% of entrepreneurs was 30 years of age or more...
The Sea Wharf Restaurant would like to determine the best way to allocate a monthly advertising budget of $1000 between newspaper advertising and radio advertising. Management decided that at least...
The Childfair Company has three plants producing child push chairs that are to be shipped to four distribution centers. Plants 1, 2, and 3 produce 12, 17, and 11 shipments per month, respectively....
Two light sources of identical strength are placed 10 m apart. An object is to be placed at a point P on a line parallel to the line joining the light sources and at a distance d meters from it (see...
The current in a wire is defined as the derivative of the charge: l (t) = Q (t). (See Example 3 in Section 3.3) What does b l (t) dt represent?
A wind force distributed against the side of a skyscraper is measured as Compute the net force and the line of action due to this distributedwind. 150 30 60 90 240 Height, 1, m Force, F(), N/m 120...
Identify the feasible region for the following set of constraints: 0.5A + 0.25B 30 1A + 5B 250 0.25A + 0.5B 50 A, B 0
An image is partitioned into two regions, one white and the other black. A reading taken from a randomly chosen point in the white section will give a reading that is normally distributed with = 4...
A particular brand of diet margarine was analyzed to determine the level of polyunsaturated fatty acid (in percentages). A sample of six packages resulted in the following data: 16.8, 17.2, 17.4,...
Trosper Tire Company decided to hire a new mechanic to handle all tire changes for customers ordering a new set of tires. Two mechanics applied for the job. One mechanic has limited experience, can...
The frame for a kite is to be made from six pieces of wood. The four exterior pieces have been cut with the lengths indicated in the figure. To maximize the area of the kite, how long should the...
The Ferguson Paper Company produces rolls of paper for use in adding machines, desk calculators, and cash registers. The rolls, which are 200 feet long, are produced in widths of 11/2, 21/2, and 31/2...
Ray Bond sells handcrafted yard decorations at county fairs. The variable cost to make these is $20 each, and he sells them for $50. The cost to rent a booth at the fair is $150. How many of these...
The diameter of bushings turned out by a manufacturing process is a normally distributed random variable with a mean of 4.035 mm and a standard deviation of 0.005 mm. A sample of 25 bushings is taken...
Upright vacuum cleaners have either a hard body type or a soft body type. Shown are the weights in pounds of a sample of each type. At a 0.05, can it be concluded that the means of the weights are...
Data were collected on the amount spent by 64 customers for lunch at a major Houston restaurant. These data are contained in the file named Houston. Based on past studies the population standard...
Ron Sargeant's electric bill from the Longwood Power Authority is shown. If his meter reading for December 17 is 52,344, find the total charges for the December bill. Include all rates and charges as...
The figure shows a beam of length L embedded in concrete walls. If a constant load W is distributed evenly along its length, the beam takes the shape of the deflection curve where E and are positive...
What percent of undergraduate enrollment in coed colleges and universities in the United States is male? A random sample of 50 such institutions give the following data (Source USA Today allege...
A plane is being tracked by radar, and data is taken every second in polar coordinates and r. At 206 seconds, use the centered finite difference (second-order correct) to find the vector expressions...
The accompanying table shows a portion of the 30 companies that comprise the Dow Jones Industrial Average (DJIA); the full data set can be found on the text website and is labeled...
A stage extraction process is depicted in Figure. In such systems, a stream containing a weight fraction Y in of a chemical enters from the left at a mass flow rate of F 1 . Simultaneously, a solvent...
A horticulturist is studying the relationship between tomato plant height and fertilizer amount. Thirty tomato plants grown in similar conditions were subjected to various amounts of fertilizer over...
To identify high-paying jobs for people who do not like stress, the following data were collected showing the average annual salary ($1000s) and the stress tolerance for a variety of occupations...
Forbelt Corporation has a one-year contract to supply motors for all refrigerators produced by the Ice Age Corporation. Ice Age manufactures the refrigerators at four locations around the country:...
Jan Gentry is the owner of a small company that produces electric scissors used to cut fabric. The annual demand is for 8,000 scissors, and Jan produces the scissors in batches. On the average, Jan...
The histogram shows the distribution of the numbers of siblings (brothers and sisters) for 2000 adults surveyed in the 2012 General Social Survey. a. Describe the shape of the distribution. b. What...
An investigation of the effectiveness of an antibacterial soap in reducing operating room contamination resulted in the accompanying table. The new soap was tested in a sample of eight operating...
Lester Hollar is vice president for human resources for a large manufacturing company. In recent years, he has noticed an increase in absenteeism that he thinks is related to the general health of...
In Hamilton County, Ohio, the mean number of days needed to sell a house is 86 days (Cincinnati Multiple Listing Service, April, 2012). Data for the sale of 40 houses in a nearby county showed a...
A subtle form of racial discrimination in housing is racial steering. Racial steering occurs when real estate agents show prospective buyers only homes in neighborhoods already dominated by that...
A high-level voltage power supply should have a nominal output voltage of 350 V. A sample of four units is selected each day and tested for process-control purposes. The data shown in Table 6E.3 give...
Compute the probability of X successes, using Table B in Appendix C. a. n = 2, p = 0.30, X = 1 b. n = 4, p = 0.60, X = 3 c. n = 5, p = 0.10, X = 0 d. n = 10, p = 0.40, X = 4 e. n = 12, p = 0.90, X =...