IQ scores on the WAIS test approximate a normal curve with a mean of 100 and a standard deviation of 15. What IQ score is identified with (a) The upper 2 percent, that is, 2 percent to the right (and...
The Global Business Travel Association reported the domestic airfare for business travel for the current year and the previous year (INC. Magazine, February 2012). Below is a sample of 12 flights...
Refer to Exercise 6.11. What is the probability that the amount of new snow will be between 2 and 4 inches? Copy the graph from Exercise 6.11, shade the appropriate area, and report the numerical...
The RAD Construction Company has been awarded a contract with the state of Delaware to replace a bridge on Pike Creek Road. Based on experience with previous projects, RAD feels the project...
A manufacturing firm has two suppliers for an electrical component used in its process: one in Mexico and one in China. The supplier in Mexico ships 82% of all the electrical components used by the...
Table P-23 in Chapter 3 contains the quarterly income before extraordinary items for Southwest Airlines for the years 1988-1999. a. Using Minitab, smooth the Southwest Airlines income data using...
Sandy Edge is president of Edge File Works, a firm that manufactures two types of metal file cabinets. The demand for the two-drawer model is 650 cabinets per week; demand for the three- drawer...
Let a. Find limx0 f (x). b. Use four-digit rounding arithmetic to evaluate f (0.1). c. Replace each trigonometric function with its third Maclaurin polynomial, and repeat part (b). d. The actual...
Consider the bottle design study situation in Exercise 11.4. and let A, B and C represent mean daily sales using bottle designs A. B, and C. respectively. Figure 11.5 gives the Excel output of a...
The operations manager of a plant that manufactures tires wants to compare the actual inner diameters of two grades of tires, each of which is expected to be 575 millimeters. A sample of five tires...
(a) Let a1 = a, a2 = f(a), a3 = f(a2) = f(f(a)), . . . an+1 = f(an), where f is a continuous function. If, limn an = L show that f(L) = L. (b) Illustrate part (a) by taking f(x) = cos x, a = 1, and...
Susan Williams has been the production manager of Medical Suppliers, Inc., for the past 17 years. Medical Suppliers, Inc., is a producer of bandages and arm slings. During the past 5 years, the...
A manufacturing company produces bearings. One line of bearings is specified to be 1.64 centimeters (cm) in diameter. A major customer requires that the variance of the bearings be no more than .001...
The Department of Statistics at Western State University offers eight sections of basic statistics. Following are the numbers of students enrolled in these sections: 34, 46, 52, 29, 41, 38, 36, and...
The routes of postal deliverers are carefully planned so that each deliverer works between 7 and 7.5 hours per shift. The planned routes assume an average walking speed of 2 miles per hour and no...
It has been reported that the average life for halogen lightbulbs is 4000 hours. Learning of this figure, a plant manager would like to find out whether the vibration and temperature conditions that...
The ogives shown are based on U.S. Census data and show the average annual personal income per capita for each of the 50 states. The data are rounded to the nearest thousand dollars. (i) Ogive (ii)...
Two catalysts may be used in a batch chemical process. Twelve batches were prepared using catalyst 1, resulting in an average yield of 86 and a sample standard deviation of 3. Fifteen batches were...
The Chartered Financial Analyst (CFA) designation is fast becoming a requirement for serious investment professionals. It is an attractive alternative to getting an MBA for students wanting a career...
A local TV station claims that 60% of people support Candidate A, 30% support Candidate B, and 10% support Candidate C. A survey of 500 registered voters is taken. The accompanying table indicates...
A television network earns an average of $1.6 million each season from a hit program and loses an average of $400,000 each season on a program that turns out to be a flop. Of all programs picked up...
Researchers wanted to determine if carpeted rooms contained more bacteria than uncarpeted rooms. To determine the amount of bacteria in a room, researchers pumped the air from the room over a Petri...
Suppose that a supplier ships components in lots of size 5,000. A single-sampling plan with n = 50 and c = 2 is being used for receiving inspection. Rejected lots are screened, and all defective...
The wedding date for a couple is quickly approaching, and the wedding planner must provide the caterer an estimate of how many people will attend the reception so that the appropriate quantity of...
Benson Manufacturing is considering ordering electronic components from three different suppliers. The suppliers may differ in terms of quality in that the proportion or percentage of defective...
In exercise 18 the data on price ($) and the overall score for six stereo headphones tested by Consumer Reports were as follows (Consumer Reports website, March 5, 2012). Brand _______________ Price...
Changes in airport procedures require considerable planning. Arrival rates of aircraft are important factors that must be taken into account. Suppose small aircraft arrive at a certain airport,...
The upward velocity of a rocket can he computed by the following formula: where = upward velocity, u = velocity at which fuel is expelled relative to the rocket, m 0 = initial mass of the rocket at...
The accompanying table shows a portion of data consisting of the selling price, the age, and the mileage for 20 used sedans. The entire data set, labeled Car_Prices, can be found on the text website....
Do business seniors at your school prepare for class more than, less than, or about the same as business seniors at other schools? The National Survey of Student Engagement (NSSE) found that business...
An entertainment company is in the planning stages of producing a new computer-animated movie for national release, so they need to determine the production time (labor-hours necessary) to produce...
For 108 randomly selected college applicants, the following frequency distribution for entrance exam scores was obtained. Construct a histogram, frequency polygon, and ogive for the data. (The data...
If water is drained from a vertical cylindrical tank by opening a valve at the base, the water will flow fast when the tank is full and slow down as it continues to drain. As it turns out, the rate...
A purchasing agent placed a rush order for a particular raw material with two different suppliers, A and B. If neither order arrives in four days the production process must be shut down until at...
In one study, physicians were asked to estimate the probability of a malignant cancer given that a test showed a positive result. They were told that the cancer had a prevalence rate of 1%, the test...
Marsha operates an expresso stand. Customers arrive according to a Poisson process at a mean rate of 30 per hour. The time needed by Marsha to serve a customer has an exponential distribution with a...
The advection-diffusion equation is used to compute the distribution of concentration along the length of a rectangular chemical reactor (see Sec. 32.1). c / t = D 2 c / x 2 U c / x kc where c =...
Consider the linear program in Problem. The value of the optimal solution is 27. Suppose that the right-hand side for constraint 1 is increased from 10 to 11. a. Use the graphical solution procedure...
The RMC Corporation blends three raw materials to produce two products: a fuel additive and a solvent base. Each ton of fuel additive is a mixture of 25 ton of material 1 and 35 ton of material 3. A...
In 2010, Apple introduced the iPad, a tablet-style computer that its former CEO Steve Jobs called a" a truly magical and revolutionary product" (CNN, January 28, 2010). Suppose you are put in charge...
While the housing market is in the tank and is not likely to emerge anytime soon, real estate investment in college towns continues to promise good returns (The Wall Street Journal, September 24,...
The annual number of industrial accidents occurring in a particular manufacturing plant is known to follow a Poisson distribution with mean 12. a. What is the probability of observing exactly 12...
Suppose you currently have a portfolio of three stocks, A, B, and C. You own 500 shares of A, 300 of B, and 1000 of C. The current share prices are $42.76, $81.33, and $58.22, respectively. You plan...
Data on salaries in the public school system are published annually in National Survey of Salaries and Wages in Public Schools by the Education Research Service. The mean annual salary of (public)...
Refer to Exercise 8.24. A city planner wants to estimate, with a 97% confidence level, the average monthly residential water usage in the city. Based on earlier data, the population standard...
In London, half of the days have some rain. The weather forecaster is correct 2/3 of the time, i.e., the probability that it rains, given that she has predicted rain, and the probability that it does...
The following data represent 15 quarters of manufacturing capacity utilization (in percentages): a. Compute three- and four-quarter moving averages for this time series. Which moving average provides...
Daves Automatic Door installs automatic garage door openers. The following list indicates the number of minutes needed to install 10 door openers: 28, 32, 24, 46, 44, 40, 54, 38, 32, and 42. (a)...
The average cost of a one-bedroom apartment in a town is $650 per month. What is the probability of randomly selecting a sample of 50 one-bedroom apartments in this town and getting a sample mean of...
A small appliance manufacturer must meet (on time) the following demands: quarter 1, 3000 units; quarter 2, 2000 units; quarter 3, 4000 units. Each quarter, up to 2700 units can be produced with...
In a Gallup poll conducted August 31September 2, 2009, 513 national adults aged 18 years of age or older who consider themselves to be Republican were asked, Of every tax dollar that goes to the...
Example 2 referred to an Ohio elevator with a maximum capacity of 2500 lb. When rating elevators, it is common to use a 25% safety factor, so the elevator should actually be able to carry a load that...
Table 6-12 on the textbook's Web site gives non seasonally adjusted quarterly data on the retail sales of hobby, toy, and game stores (in millions) for the period 1992:1 to 2008: II. Consider the...
What is the break-even point? What parameters are necessary to find it?
Gulf Coast Electronics is ready to award contracts for printing their annual report. For the past several years, the four-color annual report has been printed by Johnson Printing and Lakeside Litho....
Compute the expected number of cars arriving in Problem 14-15 using the expected value formula. Compare this with the results obtained in the simulation. Problem 14-15 The number of cars arriving per...
Commercial fish raising is a growing industry in the United States. What makes fish raised commercially grow faster and larger? Suppose that a fish industry study is conducted over the three summer...
The manufacturing company in Problem 2.20 also produces electric insulators. If the insulators break when in use, a short circuit is likely to occur. To test the strength of the insulators,...
Bill Smith is the Worthington Township manager. When citizens request a traffic light, the staff assesses the traffic flow at the requested intersection. Township policy requires the installation of...
A 50-question truefalse examination is given. Each correct answer is worth 10 points. Consider an unprepared student who randomly guesses on each question. a. If no points are deducted for incorrect...
Smokers IQ A study was conducted in which 20,211 18-year-old Israeli male military recruits were given an exam to measure IQ. In addition, the recruits were asked to disclose their smoking status. An...
A Boeing 767-300 aircraft has 213 seats. When someone buys a ticket for a flight, there is a 0.0995 probability that the person will not show up for the flight (based on data from an IBM research...
Prof. Hardtack gave four Friday quizzes last semester in his 10-student senior tax accounting class. (a) Find the mean, median, and mode for each quiz. (b) Do these measures of center agree? Explain....
According to a November 8, 2010 report on www.teleread.com, 7% of U.S. adults with online services currently read e-books. Assume that this percentage is true for the current population of U.S....
A large paper manufacturing company, the Quality Paper Corporation, has 10 paper mills from which it needs to supply 1,000 customers. It uses three alternative types of machines and four types of raw...
Mc Burger fast-food restaurant sells quarter-pounders and cheeseburgers. A quarter pounder uses a quarter of a pound of meat, and a cheeseburger uses only .2 lb. The restaurant starts the day with...
Two types of plastic are suitable for use by an electronics component manufacturer. The breaking strength of this plastic is important. It is known that 1 = 2 = 1.0 psi. From a random sample of size...
Consider the data from Exercise 11-1 on x = compressive strength and y = intrinsic permeability of concrete. (a) Test for significance of regression using a = 0.05. Find the P-value for this test....
A college infirmary conducted an experiment to determine the degree of relief provided by three cough remedies. Each cough remedy was tried on 50 students and the following data recorded. Test the...
A feed supply company has developed a special feed supplement to see if it will promote weight gain in livestock. Their researchers report that the 77 cows studied gained an average of 56 pounds and...
Economists theorize that the recent recession has affected men more than women because men are typically employed in industries that have been hit hardest by the recession, such as manufacturing and...
A random sample of 50 medical school applicants at a university has a mean raw score of 31 on the multiple choice portions of the Medical College Admission Test (MCAT). A student says that the mean...
Refer again to the data from the MBA new-matriculants survey in exercise. a. Given that a person applied to more than one school, what is the probability that the person is 2426 years old? b. Given...
Measuring the height of a California redwood tree is very difficult because these trees grow to heights over 300 feet. People familiar with these trees understand that the height of a California...
Will you expect a positive, zero, or negative linear correlation between the two variables for each of the following examples? a. Grade of a student and hours spent studying b. Incomes and...
Chelsea Truman sells celebrity magazines on Sunday morning in an area surrounded by three busy shopping centers. Demand for the magazines is distributed as shown in the following table: Chelsea has...
The diameter of holes for cable harness is known to have a normal distribution with = 0.01 inch. A random sample of size 10 yields an average diameter of 1.5045 inch. Find a 99% two-sided confidence...
With a smoothing constant of = 0.2, equation (6.2) shows that the forecast for the 13th week of the gasoline sales data from Table is given by F13 = 0.2Y12 + 0.8F12. However, the forecast for week...
Suppose you want to estimate the proportion of cars that are sport utility vehicles (SUVs) being driven in Kansas City, Missouri, at rush hour by standing on the corner of I-70 and I-470 and counting...
A psychologist determined that the number of sessions required to obtain the trust of a new patient is either 1, 2, or 3. Let x be a random variable indicating the number of sessions required to gain...
Here are boxplots of weekly gas prices for regular gas in the United States as reported by the U.S. Energy Information Administration for 2009 through 2013. a) Compare the distribution of prices over...
In a study of facial behavior, people in a control group are timed for eye contact in a 5-minute period. Their times are normally distributed with a mean of 184.0 seconds and a standard deviation of...
Heating and cooling of a building can be modeled by the ODE T' = k1(T Ta) + k2(T Tw) + P, where T = T (t) is the temperature in the building at time t, Ta the outside temperature, Tw the...
A publishing company is planning on developing an advanced quantitative analysis book for graduate students in doctoral programs. The company estimates that sales will be normally distributed, with...
It is common to ignore the thyroid gland of women during pregnancy ( New York Times, April 13, 2009). This gland makes hormones that govern metabolism, helping to regulate body weight, heart rate,...
In a Gallup poll, 1011 adults were asked if they consume alcoholic beverages, and 64% of them said that they did. Construct a 90% confidence interval estimate of the proportion of all adults who...
The cafeteria manager at a manufacturing plant has kept track of the number of cups of coffee purchased during each of the past 90 working days. a. Using the following descriptive statistics,...
Refer to the previous exercise. For the 280 African Americans in the 2008 GSS, a 99% confidence interval for the mean of EDUC is (12.38, 13.16). Explain why the following interpretation is incorrect:...
A firm has a generous but rather complicated policy concerning end-of-year bonuses for its lower-level managerial personnel. The policys key factor is a subjective judgment of contribution to...
Repeat parts (a)(d) of Exercise 11 with y = farm population and x = land area. The data file counties.dat contains information on land area, population, number of physicians, unemployment, and a...
The distribution system for the Smith Company consists of three plants (A, B, and C), two warehouses (D and E), and four customers (W, X, Y, and Z). The relevant supply, demand, and unit shipping...
On the Titanic, the probability of survival was 0.323. Among first class passengers, it was 0.625. Were survival and ticket class independent? Explain.
Norris Mill can convert logs into lumber and plywood. In a given week, the mill can turn out 400 units of production, of which 100 units of lumber and 150 units of plywood are required by regular...
Data Set 17 "Course Evaluations" in Appendix B includes data from student evaluations of courses. The summary statistics are n = 93, x = 3.91, s = 0.53. Use a 0.05 significance level to test the...
Stream cross-sectional areas ( A ) are required for a number of tasks in water resources engineering, including flood forecasting and reservoir designing. Unless electronic sounding devices are...
Refer to Figure 8.15, which shows the sensitivity report for Problem 7. a. How much would the return for U.S. Oil have to increase before it would be beneficial to increase the investment in this...
The National Safety Council released the following data on the incidence rates for fatal or lost-work time injuries per 100 employees for several industries in three recent years. Compute r for each...
In a survey of randomly selected adults, subjects were asked if they could identify at least one current member of the Supreme Court. After obtaining the results, the range rule of thumb was used to...
In the Chapter Problem, it was noted that researchers conducted a study to investigate the effects of color on cognitive tasks. Words were displayed on a computer screen with background colors of red...
The author recorded all digits selected in New Yorks Win 4 Lottery for two drawings held each day in a recent year. The frequencies of the digits from 0 through 9 are 280, 303, 331, 289, 285, 294,...