Q&A Hero

Q: The unit improvement factor is not as useful as the learning curve statistics in adjusting time estimates for learning.

Q: The unit improvement factor for a 60% learning curve at 25 units is 0.0933. The first and second timings of a person doing a job are 10 minutes and 6 minutes respectively. The learning-adjusted time estimate for the unit number 25 is 0. 9330 minutes.

Q: The unit improvement factor for a 60% learning curve at 25 units is 0.0933. The first and second timings of a person doing a job are 5 minutes and 3 minutes respectively. The learning-adjusted time estimate for the unit number 25 is 0.0933 minutes.

Q: You time someone completing a single task the first time at 100 minutes and the fourth time they do the task it takes 81 minutes. You should use a 90 percent learning curve to estimate the length of time this worker will take to complete this task in the future.

Q: You time someone completing a single task the first time at 100 minutes and the fourth time they do the task it takes 81 minutes. You should use an 81 percent learning curve to estimate the length of time this worker will take to complete this task in the future.

Q: You time someone completing a single task the first time at 120 minutes and the second time they do the task it takes 108 minutes. You should use a 90 percent Learning Curve to estimate the length of time this worker will take to complete this task in the future.

Q: You time someone completing a single task the first time at 100 minutes and the second time they do the task it takes 90 minutes. You should use a 90 percent learning curve to estimate the length of time this worker will take to complete this task in the future.

Q: You time someone completing a single task the first time at 10 minutes and the second time they do the task it takes 9 minutes. You should use an 80 percent learning curve to estimate the length of time this worker will take to complete this task in the future.

Q: An assumption of learning curves is that the time required to complete a unit will decrease at an increasing rate as the cumulative number of units completed increases.

Q: An assumption of learning curves is that the time required to complete a unit will increase at an increasing rate as the cumulative number of units completed increases.

Q: An assumption of learning curves is that the time required to complete a unit will decrease at a decreasing rate as the cumulative number of units completed increases.

Q: A learning curve shows the increase in time required for each successive unit completed.

Q: A learning curve shows the decrease in time required for each successive unit completed.

Q: On a learning curve plot, the time per unit is usually displayed on the vertical axis.

Q: A learning curve is a line displaying the way unit production time decreases as time passes.

Q: A learning curve is a line displaying the relationship between unit production time and the cumulative number of units produced.

Q: Learning curves can be applied to individuals and to organizations.

Q: Learning curves have a wide range of business applications.

Q: Learning curves only estimate the learning rates of individuals.

Q: What is the shadow price of a non-binding constraint? Why is this so?

Q: What is a "shadow price"?

Q: Two of the five essential conditions for linear programming to pertain to a real world problem are linearity and homogeneity. Discuss why these are difficult to achieve in the real world and how they might limit your confidence in the solution?

Q: Formulate and solve the following linear program. A firm wants to determine how many units of each of two products (products X and Y) they should produce in order to make the most money. The profit from making a unit of product X is $100 and the profit from making a unit of product Y is $80. Although the firm can readily sell any amount of either product, it is limited by its total labor hours and total machine hours available. The total labor hours per week are 800. Product X takes 4 hours of labor per unit and Product Y takes 2 hours of labor per unit. The total machine hours available are 750 per week. Product X takes 1 machine hour per unit and Product Y takes 5 machine hours per unit. Write the constraints and the objective function for this problem, solve for the best mix of product X and Y and report the maximum value of the objective function?

Q: Formulate and solve the following linear program. A firm wants to determine how many units of each of two products (products D and E) they should produce to make the most money. The profit in the manufacture of a unit of product D is $100 and the profit in the manufacture of a unit of product E is $87. Although the firm can readily sell any amount of either product, it is limited by its total labor hours and total machine hours available. The total labor hours per week are 4,000. Product D takes 5 hours of labor per unit and product E takes 7 hours of labor per unit. The total machine hours are 5,000 per week. Product D takes 9 hours of machine time per unit and product E takes 3 hours of machine time per unit. Write the constraints and the objective function for this problem, solve for the best mix of product D and E and report the maximum value of the objective function? Objective function: Maximize Z = $100 D + $87 E Subject to: 5 D + 7 E <= 4,000 9 D + 3 E <= 5,000

Q: The number of decision variables allowed in a linear program is which of the following? A. Less than 5 B. Less than 72 C. Less than 512 D. Less than 1,024 E. Unlimited

Q: The number of constraints allowed in a linear program is which of the following? A. Less than 5 B. Less than 72 C. Less than 512 D. Less than 1,024 E. Unlimited

Q: An objective function in a linear program can be which of the following? A. A maximization function B. A nonlinear maximization function C. A quadratic maximization function D. An uncertain quantity E. A divisible additive function

Q: Apply linear programming to this problem. A one-airplane airline wants to determine the best mix of passengers to serve each day. Their airplane seats 25 people and flies 8 one-way segments per day. There are two types of passengers: first class (F) and coach (C). The cost to serve each first class passenger is $15 per segment and the cost to serve each coach passenger is $10 per segment. The marketing objectives of the airplane owner are to carry at least 13 first class passenger-segments and 67 coach passenger-segments each day. In addition, in order to break even, they must at least carry a minimum of 110 total passenger segments each day. Which of the following is one of the constraints for this linear program? A. 15 F + 10 C => 110 B. 1 F + 1 C => 80 C. 13 F + 67 C => 110 D. 1 F => 13 E. 13 F + 67 C =< (80/200)

Q: Apply linear programming to this problem. David and Harry operate a discount jewelry store. They want to determine the best mix of customers to serve each day. There are two types of customers for their store, retail (R) and wholesale (W). The cost to serve a retail customer is $70 and the cost to serve a wholesale customer is $89. The average profit from either kind of customer is the same. To meet headquarters' expectations, they must serve at least 8 retail customers and 12 wholesale customers daily. In addition, in order to cover their salaries, they must at least serve 30 customers each day. Which of the following is one of the constraints for this model? A. 1 R + 1 W =< 8 B. 1 R + 1 W => 30 C. 8 R + 12 W => 30 D. 1 R => 12 E. 20 x (R + W) =>30

Q: Apply linear programming to this problem. A firm wants to determine how many units of each of two products (products X and Y) they should produce in order to make the most money. The profit from making a unit of product X is $190 and the profit from making a unit of product Y is $112. The firm has a limited number of labor hours and machine hours to apply to these products. The total labor hours per week are 3,000. Product X takes 2 hours of labor per unit and Product Y takes 6 hours of labor per unit. The total machine hours available are 750 per week. Product X takes 1 machine hour per unit and Product Y takes 5 machine hours per unit. Which of the following is one of the constraints for this linear program? A. 1 X + 5 Y =< 750 B. 2 X + 6 Y => 750 C. 2 X + 5 Y = 3,000 D. 1 X + 3 Y =< 3,000 E. 2 X + 6 Y =>3,000

Q: Apply linear programming to this problem. A firm wants to determine how many units of each of two products (products D and E) they should produce to make the most money. The profit in the manufacture of a unit of product D is $100 and the profit in the manufacture of a unit of product E is $87. The firm is limited by its total available labor hours and total available machine hours. The total labor hours per week are 4,000. Product D takes 5 hours per unit of labor and product E takes 7 hours per unit. The total machine hours are 5,000 per week. Product D takes 9 hours per unit of machine time and product E takes 3 hours per unit. Which of the following is one of the constraints for this linear program? A. 5 D + 7 E =< 5,000 B. 9 D + 3 E => 4,000 C. 5 D + 7 E = 4,000 D. 5 D + 9 E =< 5,000 E. 9 D + 3 E =< 5,000

Q: An agribusiness company mixes and sells chicken feed to farmers. The costs of the chicken feed ingredients vary throughout the chicken feeding season but the selling price of chicken feed is independent of the ingredients. On August 1, management needs to know how many units of each of three grains (Q, R and S) should be included in their chicken feed in order to produce the product most economically. The cost of each grain is, for a unit of Q, $30; for a unit of R, $37; and for a unit of S, $78. Applying linear programming to this problem, which of the following is the objective function? A. Minimize Z = 30 Q + 37 R + 78 S B. Maximize Z = 30 Q + 37 R + 78 S C. Minimize Z = (Q x R x S)/3 D. Minimize Z = Q + R + S E. Maximize Z = Q + R + S

Q: A company wants to determine how many units of each of two products, A and B, they should produce. The profit on product A is $50 and the profit on product B is $45. Applying linear programming to this problem, which of the following is the objective function if the firm wants to make as much money as possible? A. Minimize Z = 50 A + 45 B B. Maximize Z = 50 A + 45 B C. Maximize Z = A + B D. Minimize Z = A + B E. Maximize Z = A/45B + B/50A

Q: There are other related mathematical programming techniques that can be used instead of linear programming if the problem has a unique characteristic. If the problem prevents divisibility of products or resources we should use which of the following methodologies? A. Goal programming B. Primary programming C. Integer programming D. Unit programming E. Dynamic programming

Q: There are other related mathematical programming techniques that can be used instead of linear programming if the problem has a unique characteristic. If the problem is best solved in stages or time frames we should use which of the following methodologies? A. Goal programming B. Temporal programming C. Integer programming D. Genetic programming E. Dynamic programming

Q: There are other related mathematical programming techniques that can be used instead of linear programming if the problem has a unique characteristic. If the problem has multiple objectives we should use which of the following methodologies? A. Goal programming B. Orthogonal programming C. Integer programming D. Multiplex programming E. Dynamic programming

Q: Which of the following is a common application of linear programming in operations and supply management? A. Cycle counting analysis B. Cost of quality studies C. Cost allocation studies D. Plant location studies E. Product design decisions

Q: Which of the following is not a common application of linear programming in operations and supply management? A. Waiting time analysis B. Product planning C. Product routing D. Process control E. Service productivity analysis

Q: Which of the following is not an essential condition in a situation for linear programming to be useful? A. An explicit objective function B. Uncertainty C. Linearity D. Limited resources E. Divisibility

Q: Which of the following is an essential condition in a situation for linear programming to be useful? A. Nonlinear constraints B. Bottlenecks in the objective function C. Homogeneity D. Uncertainty E. Competing objectives

Q: Linear programming is gaining wide acceptance in many industries due to the availability of detailed operating information and the interest in optimizing processes to reduce cost.

Q: If products and resources can not be subdivided into fractions, the condition of divisibility is violated. In these cases, a modification of linear programming called integer programming can be used.

Q: If products and resources can not be subdivided into fractions, the condition of divisibility is violated. In these cases, a modification of linear programming called integral programming can be used.

Q: Finding the optimal routing for a product that must be processed sequentially through several machine centers, with each machine in a center having its own cost and output characteristics cannot be solved using linear programming.

Q: Finding the optimal product mix where several products have different costs and resource requirements cannot be solved using linear programming.

Q: Finding the optimal combination of products to stock in a retail store cannot be solved using linear programming.

Q: Minimizing the amount of scrap material generated by cutting steel, leather or fabric from a roll or sheet of stock material is one kind of problem that cannot be solved by linear programming.

Q: Finding the optimal location of a new plant by evaluating shipping costs between alternative locations and supply and demand sources is one kind of problem that can be solved by linear programming.

Q: Finding the optimal way to use aircraft and their operating crews to provide transportation services to customers to be moved between different locations is one kind of problem that can be solved by linear programming.

Q: In the formulation of a linear programming model we expect to see a requirement on all the decision variables to be either zero or some positive value.

Q: In the conventional formulation of a linear programming model we will see all of the decision variables on the right-hand-side of a constraint and a constant value on the left-hand-side.

Q: The objective function in a linear programming model can be nonlinear.

Q: Excel Solver solutions include a sensitivity report. This report gives information on making changes in objective function coefficients.

Q: Each term in a linear program's objective function should be expressed in the same units.

Q: Linear programming is useful when resources are unlimited.

Q: The decision variables in a linear programming model must be non-negative.

Q: A common application of linear programming is in materials handling.

Q: Linear programming is useless when resources are plentiful relative to demand.

Q: Linear programming is a single-objective model, meaning that it has a single objective function to be maximized or minimized.

Q: You have run a capacity resource profile on your shop. Products have been routed sequentially through resources A, B, C & D. The capacity resource profile tells you that recourse A is scheduled at 95 percent of capacity, recourse B at 80% of capacity, recourse C at 130% of capacity and recourse D at 100% of capacity. Assuming that the data we used to calculate the capacity resource profile was reasonably accurate, how would you employ the "drum, buffer, rope" thinking?

Q: Where should an in-process quality inspection be placed? Why there?

Q: In discussing batch size on an assembly line the text makes the point that "one" and "infinity" are equally correct Answers. How can this be?

Q: Describe how cost accounting is sometimes antithetical to TOC?

Q: You have run a capacity resource profile on your shop. Products have been routed sequentially through resources A, B, C & D. The capacity resource profile tells you that recourse A is scheduled at 95 percent of capacity, recourse B at 80% of capacity, recourse C at 130% of capacity and recourse D at 100% of capacity. Assuming that the data we used to calculate the capacity resource profile was reasonably accurate, what have we discovered about the process A, B, C & D?

Q: You have run a capacity resource profile on your shop. Products have been routed sequentially through resources A, B, C & D. The capacity resource profile tells you that recourse A is scheduled at 95 percent of capacity, recourse B at 80% of capacity, recourse C at 130% of capacity and recourse D at 100% of capacity. Assuming that the data we used to calculate the capacity resource profile was reasonably accurate, what would we expect to find when we go out to the shop?

Q: What are the three measurements that give guidance to the firm's operations?

Q: What are the three financial measures of the firm's ability to make money?

Q: In Goldratt's approach to project management, what is the longest set of sequential tasks called?

Q: How many rules of make up Goldratt's Rules of Production Scheduling?

Q: According to Dr. Goldratt, what is the goal of the firm?

Q: What is the rate at which money is generated by the system through sales called?

Q: What is a word indicating a resource whose capacity is less than the demand placed on it?

Q: Name the five kinds of time that make up production cycle time according to Dr. Eli Goldratt's theory of constraints.

Q: Which of the following is a negative aspect to JIT compared to synchronous manufacturing? A. JIT can not deal with outside vendors B. JIT needs broadly fluctuating production Levels C. JIT does not allow very much flexibility in the products produced D. JIT requires a great deal of workforce computational skills E. JIT does not deal well with bottlenecks

Q: A useful measure of inventory performance is called "dollar days". In which of the following areas are dollar days measurements not useful? A. Marketing B. R & D C. Manufacturing D. Project management E. Purchasing

Q: Which of the following is not an important concept in TOC? A. CCR B. Rope C. Drum D. Buffer E. File

Q: Which of the following is an approach to dealing with a bottleneck? A. Keep a buffer inventory in front of it to insure that it always has something to work on B. Use Johnson's sequencing rules on bottleneck operations C. Don't worry about the bottleneck; it will take care of itself D. Move things to a faster bottleneck E. Pay an incentive bonus to workers on the bottleneck operation

Q: According to the theory of constraints which of the following is a kind of time that makes up the cycle time in production? A. Process time B. Starting time C. Quitting time D. Information time E. Finish time

Q: According to the theory of constraints which of the following is a kind of time that makes up the cycle time in production? A. Quality time B. Idle time C. Research time D. Just-in-time E. Break time

Q: According to the theory of constraints which of the following can be a CCR? A. Factory layout B. Product design C. An employee D. A customer E. Sales literature