Culminating Experience 2 - Linear programming 3 Weeks Course Level Expectations 1.1.9 Develop, compare and apply functions using a variety of technologies (i.e. graphing calculators, spreadsheets, and on-line resources). 1.2.1 Develop and apply linear equations and inequalities that model real-world situations. 1.2.2 Represent functions (including linear and nonlinear functions such as square, square root, and piecewise defined) with tables, graphs, words and symbolic rules; translate one representation of a function into another representation. 1.2.4 Explain how changes in the parameters m and b affect the graph of a linear function. 1.2.5 Recognize and explain the meaning and practical significance of the slope and the x- and y-intercepts as they relate to a context, graph, table or equation. 1.3.1 Simplify and solve equations and inequalities. 1.3.5 Solve systems of linear equations that model real world situations using both graphical and algebraic methods. 2.1.1 Compare, locate, label and order integers, rational numbers and real numbers on number lines, scales and graphs. 2.2.2 Use technological tools such as spreadsheets, probes, algebra systems and graphing utilities to organize, analyze and evaluate large amounts of numerical information. 2.2.3 Choose from among a variety of strategies to estimate and find values of formulas, functions and roots. 2.2.4 Judge the reasonableness of estimations, computations, and predictions. 4.1.1 Collect real data and create meaningful graphical representations of the data with and without technology. Extended Course Level Expectations 1.2.7 Solve systems of linear equations that model real world situations using both graphical and algebraic methods. - is extended to systems of linear inequalities. Overview The Linear Programming Culminating Experience builds on the mathematics learned in this course and extends students’ understanding of algebra and graphing techniques to the solution of optimization problems. Students will graph the solution set of a linear inequality in two variables and solve systems of inequalities graphically by hand, and with a graphing calculator. They will identify the boundary lines, half-planes, feasible region and vertices of a feasible region and determine the objective function for a real-world problem. Students will apply the Fundamental Principle of Linear Programming (the maximum/minimum solution occurs at a vertex of the feasible region) and determine the optimal solution to real-world problems. The students’ experience solving optimization problems will result in an understanding of the historical applications and practical efficacy of linear programming and its importance in present day decision-making. Assessment Activities Evidence of Success: What students will be able to do. Students will use linear programming to identify optimal solutions to practical problems. Assessment Strategies: How will they show what they know. Homework, research questions, student presentations and a differentiated Linear Programming Problem. Launch Notes: Closure Notes: This activity provides three end-of-unit Real Life Context – assessments – two collaborative performance tasks Linear programming provides a mathematical way to and a culminating problem done individually. identify optimal conditions. Linear programming was developed out of necessity during World War II, and with In the first performance task students identify a the invention of computers, made advances into the 21st practical application and create a corresponding century. Linear programming was used, beginning with World War II and then other conflicts, to optimize the use problem. Or, to differentiate, you may select an CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 1 of 58 of resources for the military: food, vehicles, ships, personnel, etc. (View Video Clip http://www.videospider.tv/Videos/Detail/681116719.aspx or http://video.yahoo.com/watch/10072/871993). In the 1960’s Linear programming was used in the launch of the first rocket that carried an astronaut into space. In industry, linear programming is used to determine optimal solutions to many real life situations. Linear programming is a process or algorithm that determines a maximum or minimum value (optimal solution) for a linear function of more than one variable where the independent variables are subject to linear constraints. The process may be represented graphical or algebraically. In this activity we will examine the graphing approach to finding the optimal solution. application and give the student a problem to solve. Students work in small groups to apply the seven-step linear programming algorithm. They will present the solution to the class orally. The students will also submit a detailed written solution. For the second performance task, students will investigate the role of linear programming. They may research the history of linear programming, identify mathematicians who have had or may continue to have a major role in the area, or identify linear programming’s role in contemporary decision-making (See Activity Sheet 1.4b). Students will write a report about their research so that all members of the class learn more about linear programming’s development and benefits. Skits, videos, power point presentations, blogs and other creative presentation modes may be used. Interdisciplinary planning and sharing are encouraged. Students will be assessed individually through the solution of an application problem. Form A is more challenging then Form B. Important to Note: Vocabulary, connections, common mistakes, typical misconceptions Algorithm, inequality, constraint, equivalent equation and inequality, half-plane, shading, boundary line, system of equations, system of inequalities, test point, feasible region, objective function, maximum/minimum, optimization Learning Strategies Learning Activities Differentiated Instruction This investigation provides an opportunity to complete Week 1 some interdisciplinary work with the history, computer 1.1 During the first two days, provide an overview of linear programming. The rest of the week, students science, and/or English department teachers. The will hone their abilities to apply components of the history of linear programming may be researched and used in conjunction with applications and techniques seven-step algorithm using practical linear used in computer science. English department teachers programming contexts. To launch the project, may use this nonfiction project as an opportunity for students may watch the two- minute video clip students to write a research report. English teachers about army planning and the movement of goods. http://www.videospider.tv/Videos/Detail/6811167 may assist students in setting reading and writing goals. The extensive new vocabulary may be 19.aspx). supported by diagrams, graphic organizers, and a student-constructed glossary. Give students a real world problem involving transportation of military vehicles to investigate in small groups, possibly with teacher guidance. See 1.1 Activity Sheets 1.1b and 1.1c Homework is provided so that students come to class on the Activity Sheets 1.1a Defining Variables and second day with solutions and non-solutions and a Writing Constraints. Challenge the groups to graph (that has the same scaling as the one used in work together for 20 minutes and find a “best” class for the weight constraint) of the ordered pairs solution in the allotted time. Students then share for the area constraint. Two forms of the and explore all the different solutions and agree on CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 2 of 58 the one that appears to be the “best”. Then pose the question “How do we know if we have the very best solution?” Introduce the idea that there is a mathematical way to judge the solution. Have students try the first two steps of the linear programming algorithm: defining the variables and writing a constraint as well as determining solutions and non-solutions for the weight constraint. Have each group graph these on a transparency. Collect each group’s transparency. (Note: Prior to the next class, take the groups’ transparencies with the ordered pairs from the weight constraint and plot all points on one master transparency for use the next day.) homework sheet are provided. Each one has different ordered pairs so that there will be sufficient points to draw a reasonable conclusion regarding how to quickly graph the solutions of an inequality with respect to the boundary line. Teacher may also want to provide some homework examples for students who need to review x- and yintercepts of a linear function and solve some linear systems. Students will need to find x- and yintercepts and solve systems on day two to obtain the corner points of a feasible region. 1.2 Display the master transparency showing all ordered pair solutions and non-solutions to the weight constraint that the groups tested the day before. Guide students to draw the conclusion that all the solutions are on one side of the boundary line. Using Activity Sheets 1.2a Graphing the Constraints and Determining the Objective Function and student homework, each group will make a transparency for the area constraint. You may then overlay all the area constraint transparencies. Again pose a question, “Where are all the solutions to the inequality?” After students agree on the answer to that question, overlay the master weight constraint transparency onto the area constraint transparencies so students may “see” a feasible region. Then continue with the activity to complete the 7-step process. This will provide the optimal solution to the military transport problem. Have students compare it to the earlier suggested “best” solution. Then assign homework Activity Sheet 1.2b. Work from it will be used to launch the next lesson. 1.2 Keep the transparencies produced today so that future work for the feasible region can be demonstrated. Homework is provided (Activity Sheet 1.2b) where students graph the objective function for several force values is provided so students can come to the next class and see that for changing values of c in ax + by = c , it generates parallel lines. Thus, we only need to look at edges of the feasible region and ultimately just the corners of the feasible region. For students needing more practice finding x- or y-intercepts or solving systems of equations, additional homework practice may be provided. 1.3 Using Activity Sheets 1.3 The Rationale Behind Only Checking Corner Points, students will gain an understanding of the relationship of the objective function to the corner points of the feasible region; that is, that the optimal solution to a linear programming problem will be found at a corner point (vertex). Students will then apply the 7-step algorithm to a new problem, the Stop World Hunger Fundraiser. 1.3 Emphasize the need to check the final answer with the actual problem to be sure it is indeed the solution. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Time may be short for completing the Stop the World Hunger problem in section 3 of Activity Sheet 1.3. You may want to prepare a solution to this problem ahead of time and walk the students through the process up to the graph of the feasible Page 3 of 58 The URL below dynamically demonstrates objective function lines moving in parallel fashion. It may be used here or with Activity 1.5 below http://people.richland.edu/james/ictcm/2006/slope. html 1.4 Students may watch a video about the manufacture of Belgian chocolates. You may use the video at www.metalproject.co.uk/METAL/Resources/Film s/linear_programming/index.html. (produced by Mathematics to Enhance Economics: Enhancing Teaching and Learning). You may pause the video and have students do the associated linear programming problem and then restart the clip to "see" the solution. Or you can just let the teacher in the video talk students through the problem-- it is done slowly and with clarity. The problem has a fractional solution, which is fine since the company can produce a fraction of a batch of chocolate. For the next problem of the day, Activity Sheets 1.4a Eduardo’s Jobs, is provided. At this point it is time to describe the research activity and the research questions. Students should take a few days to select a topic of interest. Activity Sheets 1.4b Suggested Research Question List gives some ideas. region (steps 1 – 4). Then, you can have the students carry out steps 5, 6 and 7 to gain practice with the final steps of the linear programming algorithm. Many students are overwhelmed with the amount of reading in a linear programming problem. You may prompt students needing assistance by verbally (or with highlighter) highlighting the sentences that contain the variable definitions or constraints. For example, “The first constraint uses the statement ‘No more than 100 shirts can be made’.” In order to quickly sketch the boundary line, students should be reminded that the intercepts are easy to find because the boundary equations are generally in standard form. Emphasize the use of the “test point”; i.e. graph the boundary line and then use one “test” point. If the inequality is satisfied, that is the side that contains the entire solution set. If the inequality is not satisfied then the other side of the line contains the solutions. The boundary line is included since we are graphing ax + by ≤ c or ax + by ≥ c. Often the origin can be used as the test point. The use of a test point extends to solving a system of two constraints where one needs to examine a test point in each of the four regions created by 2 intersecting lines. 1.4 Students may begin their research of LP in general, or learn about George Dantzig and his contributions to linear programming (see Activity Sheet 1.4b). Again, you may want to emphasize that linear programming is used daily and recent advancements have been made in the field. Linear programming software is used to aid in finding optimal solutions in many industries. The following website may be used to give insight into who is using it and why: http://www.ilog.com/products/optimization/. See the end of the unit plan for some research questions. The teacher may continue to assist those students challenged by the reading by verbally highlighting CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 4 of 58 or physically highlighting important key phrases such as “Combined he will work a total of 12 hours a week at the two jobs.” 1.5 Make sure that students are considering the many topics they can research so that by early in the second week in this unit, actual research can begin. See the choice of videos and descriptions is in the teacher notes at the right. Another problem with the 7-step support template has been provided (see Activity Sheets 1.5: The Farmer). This feasible region does not have corners at the origin or on the x or y axis. By next class students can provide their own “template” for assigned problems. However, see teacher note at right. This day may be needed to reinforce the idea that the process used to solve this problem “fits the same mold” as those presented thus far. 1.5 You may emphasize that linear programming problems (now often called operations research) are seen in many real world contexts where a maximum or minimum solution is sought: transportation, manufacturing, agriculture, business, health care, advertising, military, telecommunications, financial services, energy and utilities, marketing and sales. See www.hsor.org for a very rich site: the Mathematics for Decision Making in Industry and Government, the High School Operations Research site. It has modules from Bethlehem Steel, the Meat Industry, LL Bean, and Special Education School Buses. Videos are available too. Most materials are for free. There are some that can be purchased. This site was a link from the NCTM illuminations site Activity Sheet 1.5, The Farmer, is a challenging problem in which only one of the constraints is in the form ax by c . The second constraint is y x . Furthermore, instead of the nonnegative constraints x 0 , y 0 , The Farmer requires the constraints x 100 , y 100 . Therefore, if during the first 4 days of the unit, time has not permitted the class to investigate all problems listed in 1.3 and 1.4, you may instead decide to use this day to catch up with those problems. Or, you may decide to replace The Farmer with the first supplemental problem listed at the end of the unit plan. (See Activity Sheets 1.5b). This problem, about an artist, has a style much like those addressed so far in the unit. The URL below (also cited in 1.3 above) reinforces the relationship between the objective function and the corner points of the feasible region and it opens up the discussion of what happens when the slope of the graph of an objective function is equal to the slope of an edge. In week 2 activities, one of the recommended problems has an edge parallel to the objective function CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 5 of 58 http://people.richland.edu/james/ictcm/2006/slope.html Week 2 1.6 Sometime during this 3-day period, it is hoped that students can be provided with some library time and/or computer time to work on their research question. Students should also be given a copy of the research rubric, Activity Sheet 1.4c that will be used to assess their project. Students should begin Activity Sheets Farm Subsidies 1.6a in class. The teacher may want to check the students’ constraints before they delve too deeply into the problem. The same set of constraints applies to A1, A2 and B. A2 may be assigned for homework and B may be assigned for homework for students ready for a challenge. Or part B might be done in class. Problem B illustrates that when two adjacent corners both produce the optimum result, then all points along the entire edge do also. If the video listed above in Activity 1.5 was shown in class, students will have been forewarned of this possibility. Research questions should be selected and assigned by the beginning of week two and some class time may be scheduled for computer lab or library work in this three-day period. Students may begin to work in groups on a research question. Following the activity about the farm subsidies, you may share the lesson about the tomato farmer from the video at www.metalproject.co.uk/METAL/Resources/Film s/linear_programming/index.html. A supplemental problem, Activity Sheet 1.6b Natasha’s Cat, requires students to minimize an objective function. The coordinates of one of the corner points are fractions, but make sense since one can feed a cat a half serving of cat food. Sources for more problems to try during this threeday period are provided at the right. And a few problems are provided on Activity Sheet 1.5b.It is recommended that students provide their own template for these. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 1.6 You may need to monitor groups closely on the construction of the constraints in Activity 1.6. The students should be alerted to look for three constraints in addition to the non-negative constraints. And, when students are creating their graphs, you may need to remind students to label their lines clearly so that they know which line matches each constraint. This will help in formulating the equations that are used to find the intercepts. During Activity 1.6, you might ask students to look up farm subsidies and ask if farmers in other countries get subsidies, what crops are subsidized, and if any farmers in Connecticut get one. See a farm subsidy database at http://farm.ewg.org/farm/region.php?fips=09003. The tomato farmer video contains three constraints in addition to non-negative constraints. Select 4.04 and 4.05 at www.metalproject.co.uk/METAL/Resources/Films /linear_programming/index.html You may just show the greenhouses and situation (4 minutes) and do the problem in class or you can let the economics teacher in the video do the problem (12 – 16 minutes). The ultimate solution is to not introduce lettuce farming, similar to problem A1 in Activity Sheet 1.6a where the optimal solution is to plant only oats. Natasha’s cat uses the AAFCO guidelines for felines and is based on dry matter values. There may be a need to do some review work with percents to determine which cat food really does provide the most protein (or other nutrient). Students ready for a challenge may be provided with problems that have more than two constraints in addition to the non-negative constraints or may be directed to www.hsor.org mentioned in 1.5 or to the dirt bike activity cited in the resources at the end of this plan http://illuminations.nctm.org (Go under grade 9 – 12 algebra and select Dirt Bike Dilemma.) See Activity Sheets 1.5b Supplemental Problem List for alternative problem ideas. Page 6 of 58 Now is a good time to administer, score and share solutions to the Unit Test problems. To differentiate the assessment, two versions are provided. 1.7 In preparation for the final presentations on the research questions, students should be encouraged to create skits, videos, power point presentations, etc. In addition to the time that students are spending on their research question, students should also be encouraged to create their own linear programming problem individually or in pairs. Then ideally have the two students or pairs of students join to form a group. They will select and solve one of the two problems and share the problem and its solution with the class. A written solution should also be collected from each group See the Activity Sheet 1.7a, Create Your Own Linear Programming Problem for ideas. A rubric, Activity Sheets 1.7b, for the solution should be given to the students and used as a selfassessment and reflection of progress. 1.8 All groups report out on the final research questions. Any student-created skits, videos etc. are shared with the class. Written reports are due. To motivate students while they continue their study of linear programming, you may wish to use the following video on Operational Research http://www.bnet.com/2422-13950_23-178846.html - the individual in this video worked with George Dantzig at Stanford University. 1.7 Given that time has been allocated to research already in Activity 1.6 and that four additional days are provided here in Activity 1.7, it is recommended that, in addition to the research question, all students work in small groups (2-3 students – perhaps their research teams) to create their own linear programming problem. If students struggle in creating their own problem, the teacher may have them choose from Activity Sheets 1.5b Supplemental Linear Programming Problems list at the end of the unit plan. 1.8 Focus should be on sharing the work that the students researched and studied in groups. The goal is to have students leave with new knowledge and new questions, and some questions which might remain unanswered. Leave time for discussion and posing, “What if’s?” Guests may be invited to share interesting business and industry applications and see the work your students have accomplished. For the presentations related to the linear programming problems that were created, students should explain each of the steps used in solving their problem, i.e. follow the algorithm. See Activity Sheets 1.4d for the rubric for the research presentation and Activity Sheets 1.7b for the rubric for the “create your own linear programming problem” presentation. Resources: http://www.videospider.tv/Videos/Detail/681116719.aspx (1.1) http://people.richland.edu/james/ictcm/2006/slope.html (1.3, 1.5) Belgian Chocolates and Tomato Farmers videos (produced by Mathematics to Enhance Economics: Enhancing Teaching and Learning – at www.metalproject.co.uk/METAL/Resources/Films/linear_programming/index.html (1.4, 1.6) The following website may be used to give insight into who is using linear programming and why: http://www.ilog.com/products/optimization/. (1.4) See www.hsor.org for many high school linear programming problems and information on linear programming (1.5) Contemporary College Algebra: Data, Functions, Modeling, 6th ed., McGraw – Hill Primis Custom Publishing . Don Small author (Farm Subsidy problem, 1.6) CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 7 of 58 Farm subsidy data base at http://farm.ewg. org/farm/region.php?fips=09003 (1.6) video on Operational Research use in 1.6 or later- http://www.bnet.com/2422-13950_23-178846.html TI Activity Exchange for Design your Own Can at http://education.ti.com/ educationportal/activityexchange/ Activity.do?aId=8272&cid=US (supplemental problem #2) http://illuminations.nctm.org (supplemental problem #3) http://www.wikihow.com/Make-a-Duct-Tape-Wallet http://www.ducttapefashion.com/products/prod01.htm (supplemental problem #4) TI Numb3rs Linear Programming Activity at http://education.ti.com/educationportal/activityexchange/Activity.do?cid=US&aId=7508 (supplemental problem #6) Bakers Choice published by Key Curriculum Press (supplemental problem #7) Information relevant to George Dantzig: http://www.lionhrtpub.com/orms/orms-8-05/dantzig.html and http://www.lionhrtpub.com/orms/orms-6-05/dantzig.html (Suggested research question #4) CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 8 of 58 Unit 8: Culminating Experience 2: Linear Programming Activity 1.1a, p. 1 of 4 Defining Variables and Writing Constraints Name: _________________________________________ Date: _________________ Section 1: The Peacekeeping Problem Read the following problem. Your team will have approximately 20 minutes to explore the following problem and offer a possible “best” solution. The UN needs to move a number of units of Hummers (one unit has 5 Hummer vehicles), and Apache helicopters, for air support, to a region in the world for peacekeeping purposes. A ship is used to transport these vehicles and can accommodate a total equipment weight of 150 tons. Each Hummer unit weighs 15 tons and each Apache helicopter weighs 6 tons. Each Hummer unit uses an area of 1,200 square feet and each helicopter uses an area of 1,800 square feet. The ship has a total of 25,200 square feet of area to use for transport. What combination of Hummer units and Apache helicopters will produce a maximum force (force = the sum of Hummer units and helicopters) of Hummer units and Apache helicopters for the UN? After working in your group, please submit this sheet with the information below completed and all calculations (there is room on the back): Group Member Names: Number of Hummer units to transport: Number of Apache helicopters to transport: Is the weight of the Hummer units and Apache helicopters (using the number of units you claim) give a maximum force less than or equal to 150 tons? ____ Show your calculation. Is the total area (square feet) for the number of Hummer units and Apache helicopters (using the number of units you claim) give a maximum force less than or equal to 25200 square feet? _____ Show your calculation: Why do you think you have the best possible combination of vehicles that maximizes the force for the UN? CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 9 of 58 Unit 8, Culminating Experience 2 Activity 1.1a, p. 2 of 4 Section 2: Defining Variables and Writing the First Constraint--Weight After examining each team’s “best” solution, we have now identified the “best” solution put forth by this class. But how do we know that this is the best possible solution (i.e. the “optimal” solution)? While we may not be able to answer this question in the remainder of this class period, there is indeed a mathematical technique called linear programming that will allow us to find the optimal solution. There are seven steps in this process. Today we will examine the first two. The first step in the algorithm for solving a linear programming problem is to define variables for the unknowns in the problem. For example, There are two kinds of vehicles that need to be transported: units of Hummers and Apache helicopters. Let x represent the number of Hummer units to be transported. Let y represent the number of Apache helicopters to be transported. The second step is to use these defined variables to write the constraints for the problem. A ship is used to transport these vehicles and can accommodate a total equipment weight of 150 tons. Each Hummer unit weighs 15 tons and each Apache helicopter weighs 6 tons. Weight Constraint: 15x + 6y < 150 1. It may be helpful to build a table and explore combinations of vehicles to find possible solutions. A possible solution is a pair of values for x and y which satisfy the constraint. Continue filling in the table, finding solutions to the constraint for this problem. Each member of the team should find their own three pairs of values. Number of Hummer units to be transported, x Number of Apache helicopter to be transported, y Weight Constraint 15x + 6y < 150 Solution to the Constraint? 4 10 8 20 15 (4) + 6(8) ≤ 150 15 (10) + 6(20) ≤ 150 Yes No CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 10 of 58 Unit 8, Culminating Experience 2 Activity 1.1a, p. 3 of 4 2. Since the solutions to the problem must satisfy all conditions in the problem, and there cannot there be a negative number of units of Hummers nor can there be a negative number of helicopters, this means that even though (-1, -2) satisfies 15x + 6y ≤ 150, we would not consider it to be a solution to our peacekeeping problem nor would we graph it as a solution of the problem. Write inequalities that state (1) that the number of units of Hummers cannot be negative and (2) that the number of Apache helicopters cannot be negative. _____________________________________________ 3. Using the graph paper below, label the axes on the graph and plot the points from your table. Note: that the graph is not a graph of the entire plane because we do not want points that have one or both coordinates negative. Use green to plot each ordered pair that represents a solution to the constraint. Use red to plot each ordered pair that did not result in a solution to the constraint. Graph the equation 15x + 6y = 150. The line you get is called a boundary line. Make a conjecture about the location (with respect to the boundary line) of the points on the graph that represent solutions to the weight constraint, 15x + 6y ≤ 150. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 11 of 58 Unit 8, Culminating Experience 2 Activity 1.1a, p. 4 of 4 Section 3: More team work 1. Within each team, pool the team’s data (from member’s tables and the work getting a best solution) using green dots for points whose coordinates are solutions and red dots for points whose coordinates are “not possible.” Make sure you are plotting the points on your individual graphs while the team recorder makes a graph of the team data on a team transparency. You will need the graphs and transparency next class. 2. Graph the boundary line for the weight constraint if you have not already. 3. You may not have been able to make a conjecture with just your own data, but with all the team members’ data, you should be able to make a conjecture about the location (with respect to the boundary line) of the points on the graph that represent solutions to the weight constraint, 15x + 6y ≤ 150. 4. Is it necessary to find a lot of solutions of 15x + 6y < 150 in order to make the graph of this inequality? How many solutions do we need to find, assuming we have plotted the boundary line? 5. There is a second constraint for this problem. Using the sentence, “Each Hummer unit uses an area of 1,200 square feet and each helicopter uses an area of 1,800 square feet. The ship has a total of 25,200 square feet of area to use for transport.” Write an inequality to define this area constraint. _______________________________________ For homework you will need to make a table and graph for the second constraint. Bring it to class tomorrow so we can find that “best” solution. A table and graph sheet will be distributed. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 12 of 58 Unit 8, Culminating Experience 2: Linear Programming Homework 1.1b, p. 1 of 2 Defining Variables and Writing Constraints Name: __________________________________________ Date: __________________ In class you defined the variables for the Peacekeeping Problem. Let x represent the number of Hummer units to be transported. Let y represent the number of Apache helicopters to be transported. Near the end of class you wrote the constraint 1200x + 1800 y ≤ 25200 using the sentence, “Each Hummer unit uses an area of 1,200 square feet and each helicopter uses an area of 1,800 square feet. The ship has a total of 25,200 square feet of area to use for transport.” 1. It may be helpful to build a table to explore combinations of vehicles and possible solutions as you did in class for the weight constraint. A possible solution is a pair of values for x and y which satisfy the constraint. Continue filling in the table, finding solutions to the constraint for this problem. Select two points of your choice for the last two rows. Number of Hummer units, x Number of Apache helicopters, y Area Constraint 1200x + 1800y < 25200 Solution? 4 10 2 6 4 9 8 20 2 8 6 5 1200 (4) + 1800(8) ≤ 25200 1200 (10) + 1800(20) ≤ 25200 Yes No 2. Using the graph paper below, label the axes on the graph and plot the points from your table. Use green to plot each ordered pair that represents a solution to the constraint. Use red to plot each ordered pair that is not a solution to the constraint. Next, graph the equation 1200x + 1800y = 25200. (or the equivalent equation 2x + 3y = 42) The resulting line is called a boundary line. Make a conjecture about the location (with respect to the boundary line) of the points on the graph that represent solutions to the area constraint 1200x + 1800y ≤ 25200. _____________________________________________________________________ CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 13 of 58 Unit 8, Culminating Experience 2 Homework 1.1b, p. 2 of 2 ______________________________ ______________________________ ______________________________ CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 14 of 58 Unit 8: Culminating Experience 2 Homework 1.1c, p. 1 of 2 Defining Variables and Writing Constraints Name: ____________________________________ Date: ____________________ In class you defined the variables for the Peacekeeping Problem. Let x represent the number of Hummer units to be transported. Let y represent the number of Apache helicopters to be transported. Near the end of class you wrote the constraint 1200x + 1800 y ≤ 25200 using the sentence, “Each Hummer unit uses an area of 1,200 square feet and each helicopter uses an area of 1,800 square feet. The ship has a total of 25,200 square feet of area to use for transport.” 1 It may be helpful to build a table to explore combinations of vehicles to find possible solutions as you did in class for the weight constraint. A possible solution is a pair of values for x and y which satisfy the constraint. Continue filling in the table, finding solutions to the constraint for this problem. Select 2 points of your choice for the last 2 rows. Number of Hummer units, x Number of Apache helicopters, y Area Constraint 1200x + 1800y < 25200 Solution? 4 10 1 6 3 10 8 20 2 12 15 8 1200 (4) + 1800(8) ≤ 25200 1200 (10) + 1800(20) ≤ 25200 Yes No 2 Using the graph paper below, label the axes on the graph and plot the points from your table. Use green to plot each ordered pair that represents a solution to the constraint. Use red to plot each ordered pair that is not a solution to the constraint. Next, graph the equation 1200x + 1800y = 25200 (or the equivalent equation 2x + 3y = 42). The resulting line is called a boundary line. Make a conjecture about the location (with respect to the boundary line) of the points on the graph that represent solutions to the area constraint 1200x + 1800y ≤ 25200. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 15 of 58 Unit 8, Culminating Experience 2 Homework 1.1c, p. 2 of 2 ______________________________ ______________________________ ______________________________ CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 16 of 58 Unit 8: Culminating Experience 2 Activity 1.2a, p. 1 of 5: Graphing the Constraints and Determining the Objective Function Name: _______________________________________ Date: _____________________ Section 1: A class graph Last class we found the best team solution to the UN peacekeeping problem by the guess, check and revise method. Let us continue our study of linear programming so we can find the best solution. (We may have found it already, but we do not know we have.) Each team recorder made a transparency of the points their team used for the weight constraint. The team recorders also drew in the boundary line of the weight constraint. Let us overlay all the transparencies. 1 You should see a pattern with regard to the location of the solutions and the boundary line emerging. What is it? Section 2: The Second Constraint--Area The UN needs to move a number of units of Hummers (one unit has 5 Hummer vehicles), and Apache helicopters, for air support, to a region in the world for peacekeeping purposes. A ship is used to transport these vehicles and can accommodate a total equipment weight of 150 tons. Each Hummer unit weighs 15 tons and each Apache helicopter weighs 6 tons. Each Hummer unit uses an area of 1,200 square feet and each helicopter uses an area of 1,800 square feet. The ship has a total of 25,200 square feet of area to use for transport. What combination of Hummer units and Apache helicopters will produce a maximum force of Hummer units and Apache helicopters for the UN? Let x represent the number of Hummer units to be transported. Let y represent the number of Apache helicopters to be transported. Weight constraint: 15x + 6y < 150 Area constraint: 1200x + 1800y ≤ 25200 Implied constraints x ≥ 0, y ≥ 0 Last night you completed a table, looking for solutions to our area constraint, 1200x + 1800y ≤ 25200. You also made a graph. 1. Using a new transparency, make a team graph for the points your team members tested last night for the weight constraint. When plotting coordinates from your tables, plot points whose coordinates are solutions in green and “not possible” points in red. Also be sure to draw the graph of the boundary line, 1200x + 1800y = 25200. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 17 of 58 Unit 8, Culminating Experience 2 Activity 1.2a, p. 2 of 5 2. Now, let’s pool the class data by overlaying the team transparencies. You should see a pattern with regard to the solutions and the boundary line developing. What is it? 3. Is it necessary to find a lot of solutions of 1200x + 1800y < 25200 in order to make the graph of this inequality? How many do we need to find, assuming we have plotted the boundary line? Now that you can graph a constraint, you have almost mastered the third requirement to be able to solve a linear programming problem graphically. Section 3: Graphing All Constraints Simultaneously For the Peacekeeping Problem We are going to continue to develop our understanding of constraints and their graphical representations. The third step of the linear programming algorithm requires that we graph all constraints on the same axes. The region containing just the points that satisfy all the constraints simultaneously (hence the solutions to the system of inequalities) is called the feasible region. Let x represent the number of Hummer units to be transported. Let y represent the number of Apache helicopters to be transported. Weight constraint: 15 x + 6y < 150 Area constraint: 1200x + 1800 y ≤ 25200 Implied constraints x ≥ 0, y ≥ 0 Last night, your teacher made a master graph of all points plotted for the weight constraint using each team’s transparency from the prior day’s lesson. Your teacher will now place the master transparency for the weight constraint on top of the team transparencies for the area constraint. You should see a region in the shape of a quadrilateral that appears to have only points that are green. Some parts of the first quadrant will have only red points; others will have red and green points. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 18 of 58 Unit 8, Culminating Experience 2 Activity 1.2a, p. 3 of 5 1. Our feasible region is the quadrilateral region that has only green points. Why? Below is a graph of the first quadrant with the boundary lines of the two inequalities. Region B contains all the possible solutions of our peacekeeping problem. You have now completed step three because you have identified the feasible region. You now have a graph of all the solutions of x ≥0, y ≥ 0, 15x + 6y ≤ 150, and 1200x + 1800y ≤ 25200. Usually we would lightly shade in region B. Do so now. Section 4: Corner points: So far we have completed the following steps 1. Clearly define each variable to be used in the constraints. 2. Develop all constraints. Recall that many real world problems must include the constraints of x > 0 and y > 0. 3. Graph the system of inequalities to obtain the feasible region. Be sure to label the graph and shade the feasible region. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 19 of 58 Unit 8, Culminating Experience 2 Activity 1.2a, p. 4 of 5 4. The four vertices (corner points) of region B are very important. Finding their coordinates is our fourth step. Next class we will explore in greater detail just why. But today we would like to just get an overview of the procedure so we can find out if any team got the optimal solution. As you find the intersections, remember you can use the equivalent system: area constraint line, 2x + 3y = 42 and weight constraint line, 5x + 2y = 50. Why? Region B is bounded by sections of the four boundary lines of our constraints. 1. The boundary lines x = 0 and y = 0 intersect at the origin whose coordinates are: _________________ 2. The area constraint line 1200 x + 1800 y = 25200 (equivalently 2x + 3y = 42) and x = 0 meet at the y-intercept of the area constraint line. That y –intercept is _________________ 3. The weight constraint line with equation 15x + 6y = 150 (equivalently 5x + 2y = 50) and x = 0 meet and the weight constraint’s x-intercept which is _____ 4. Lastly the weight constraint line with equation 15x + 6y = 150 and the area constraint line whose equation is 1200x + 1800y = 25200 meet at __________. Finding this corner point will require a little work. You will have to solve a system of equations. The algebra will be simpler if you use the equivalent system given above. 5. Label the points with their coordinates on the graph on page 3. Section 5: The Objective Function and the Linear Programming Model Even though we have identified all the ordered pairs whose coordinates satisfy all the constraints, we now need to be able to select the best (optimal) solution. When you were working as teams last class, you found there was one sentence in the problem that helped you to determine whether one solution you obtained was better than another one. This leads us to our fifth step. For the fifth step we need to reread the problem looking for an “objective function,” a quantity that needs to be maximized or minimized. For the UN peacekeeping problem, our objective is to maximize the force of Hummer units and Apache helicopters that we can transport. We need to write an equation for that which we are maximizing (in our case, force) in terms of the variables that we used to define the constraints (in our case, number of Hummer units (x) and number of Apache helicopters (y)). When we have a linear function that must be optimized (in other words minimized or maximized) subject to linear constraints (our linear inequalities), we have a linear programming model. Our peacekeeping problem meets these conditions. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 20 of 58 Unit 8, Culminating Experience 2 Activity 1.2a, p. 5 of 5 Let us define an objective function. It is linear. Reread the problem. The important sentence for the definition of the objective function is: “What combination of Hummer units and Apache helicopters will produce a maximum force of Hummer units and Apache helicopters for the military?” Note: The “force” is sum of the number of Hummer units and the number of Apache helicopters. Force = Section 6: The Solution to our Peacekeeping Problem Tomorrow we will demonstrate why of all the many points in the feasible region, the only ones we need to examine to find the maximum function value or minimum function value are the ones at the corners. If we evaluate our objective function at each of the corners and take the coordinates that give us the largest value, we will get the maximum force for our peacekeeping problem, the sixth step in this algorithm. 1 Now evaluate the objective function Force = x + y at (0,0), (0, 14), (10, 0) and (6, 10). What is the maximum force? Section 7: Sixth of the seven linear programming steps So far we have completed the following steps: 1. Clearly define each variable to be used in the constraints. 2. Develop all constraints. Recall that many real world problems must include the constraints of x > 0 and y > 0. 3. Graph the system of inequalities to obtain the feasible region. Be sure to label your graph and shade the feasible region. 4. On the graph, find and label the corner points with their coordinates. 5. Define the objective function. 6. Now evaluate the objective function f = ax +by at all corner points. Make a table or use the table feature of your grapher. What is the maximum or minimum value? Next class we will examine the rationale behind step 6 and add the important step 7. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 21 of 58 Unit 8, Culminating Experience 2 Homework 1.2b, p. 1 of 1 Name ____________________________ Date _________________________ We determined in class that the objective function for the peacekeeping problem is: F= x+y 1. Let F = 1 and graph x + y = 1 on the graph below. 2. Let F = 3 and graph x + y = 3 on the graph below. 3. Select 3 more values for F and graph each resulting equation. Show your work and equations below. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 22 of 58 Unit 8: Culminating Experience 2 Activity 1.3, p. 1 of 6 The Rational Behind Only Checking Corner Points Name: _____________________________________ Date: __________________ Today we will revisit our peacekeeping problem. We will first examine the rationale behind testing just the corner points for a largest or smallest function value, and we will then make sure our answer does indeed make sense for the problem (the seventh and final step in this linear programming algorithm). Lastly as we apply all our steps to a new problem, we will determine an efficient method for locating the feasible region. Section 1: Why Only Evaluate at the Corner Points? Last night you made a careful graph of the peacekeeping problem’s constraints and each of you was asked to draw three Force lines on your graphs. Our goal is to define a method that will always identify the optimal solution within the feasible region. The key to the answer is the objective function. In our case, the objective function is Force = x + y where x represents the number of Hummer units and y represents the number of Apache helicopters. While making a table of the coordinates of some of the points in the feasible region and evaluating the objective function at those points provides insight into the problem, this process will not let us know if we have found the maximum or minimum value of the objective function. However, it does provide the insight we need to understand why we only need test the corner points. # Hummer units, x 0 2 4 6 # helicopters, y 6 4 6 8 Force = x + y Force = 0 + 6 = 6 Force = 2 + 4 = 6 Force = 4 + 6 = 10 Force = 6 + 8 = 14 Each of the points whose coordinates are in the table belongs to a particular Force line. In the table above, both (0, 6) and (2, 4) are on the line x + y = 6. Since the coordinates of all points on each line are always going to produce the same Force, note that our line intersects points on the edges of the feasible region as well as interior points, so the interior points can be ignored and we can just use the coordinates of an edge (a boundary point). For our example, there is no need to test (2, 4), an interior point because it is on the same line as (0, 6). See the graph on the next page. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 23 of 58 Unit 8, Culminating Experience 2 Activity 1.3: p. 2 of 6 In the same manner (7, 0) and (1, 6) both deliver the same Force and are on the same Force line x + y = 7. Again, we can just use the boundary point (7, 0). So now we know we only need to examine all points on the edges of our polygon. However that is still too many (an infinite number to be exact). CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 24 of 58 Unit 8, Culminating Experience 2 Activity 1.3, p. 3 of 6 Each of you graphed three Force lines for homework. Compare your lines with those of a neighbor. Notice all the Force lines are parallel to each other. Since the coordinates of any point on a given line are going to always produce the same Force, the greatest Force will occur on the line that intersects the feasible region with the largest Force. Using the edge of a ruler as a model of a force line, continue to “move” the ruler in parallel fashion (and so the F amounts get larger) until it only touches the feasible region at one point, and so that if you continued to move it, it would no longer intersect the feasible region. What is special about the one point you got? See the graph below. For our peacekeeping problem, the point with coordinates (6, 10) gives us the largest value, Force = 16. We can see graphically that this is where the line x + y = 16 will intersect the feasible region in exactly one point. For values less than 16 but greater than or equal to zero the Force lines will intersect the region in an infinite number of points. And for values greater than 16, the force lines will not intersect the feasible region at all. We do not usually graph the objective function f. Because we know that a maximum or minimum for the function must occur at a corner point, we merely find the coordinates of all corner points and evaluate the objective function at each point. If there are a lot of corner points (there would need to be more constraints), we can use our calculator’s table feature to evaluate the objective function. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 25 of 58 Unit 8, Culminating Experience 2 Activity 1.3, p. 4 of 6 Lastly, as with all real world problems, we step back and make sure that the solution we are proposing makes sense for the problem we are solving. It is always wise to be sure the coordinates of the ordered pair do indeed satisfy the constraints, that we have evaluated the objective function correctly, and that we have included appropriate units in our answer. Section 2: The Seven Steps of the linear programming algorithm We have now completed the steps in the linear programming process: 1. Clearly define each variable to be used in the constraints. 2. Define all constraints. Recall that many real world problems must include the constraints of x > 0 and y > 0. 3. Graph the system of inequalities and shade the feasible region. 4. On the graph, determine and label the corner points with their coordinates. 5. Define the objective function 6. Now evaluate the objective function f = ax + by at all corner points. Make a table or use the table feature of your grapher. What is the maximum or minimum value? 7. Step back and make sure your solution makes sense. Then state your solution and make sure to use appropriate units. Section 3: The “Stop World Hunger Fundraiser” Problem Let us apply our new linear programming algorithm to a new problem. Read the problem below and identify the variables. The Say No to World Hunger committee has decided to have a fund raiser next month. The idea for the fund raiser is to make and sell t-shirts with tie-dyed designs. There are two designs being offered: a child’s face and a custom design. No more than 100 shirts can be made and production may not cost over $560. It costs $5 to make a child face design tie-dye and $7 to make a custom designed tie-dye. The profit for a child’s face design t-shirt is $3.50 per shirt. The profit for a custom design t-shirt is $5.00 per shirt. Find the maximum possible profit from the fund raiser. 1. The variables are: x is y is CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 26 of 58 Unit 8, Culminating Experience 2 Activity 1.3: p. 5 of 6 2. Now write the four inequalities (do not forget the non-negativity constraints) that constrain the problem. 3. Graph the constraints. Apply the “test” point principle by identifying four points, each one being clearly in the region you wish to test. Use the origin for one of the test points. Write down your four test points and determine if its coordinates satisfy BOTH constraints. There is only one region for which that will happen. Shade the feasible region. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 27 of 58 Unit 8, Culminating Experience 2 Activity 1.3, p. 6 of 6 4. Find the coordinates of the corner points. Some will be intercepts of the constraint lines. For one corner you will need to solve a system of equations. Show your work here. 5. Write down your objective function. 6. Now make a table of values for the corner points and select the corner that gives you a maximum. x y Profit = 7. Write down the solution after you have checked to be sure it does make sense. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 28 of 58 Unit 8: Culminating Experience 2: Activity 1.4a, p. 1 of 3 Eduardo’s Jobs Name: ____________________________ Date: _________________________ Eduardo is a high school student who is going to work two jobs this summer. He will be a painter for one job and will mow lawns for the second job. Combined he will work a total of at most 24 hours a week at the two jobs. For his first job, painting, he has found that he needs 1.5 hours of preparation time for every hour he works. He is not paid for the prep time and so does not count this in his hours of work. For his second job, mowing, he needs 0.5 hour of preparation time for every hour he works. He wants his total preparation time to be at most 18 hours per week. If Eduardo makes 12 dollars an hour painting and 9 dollars an hour mowing lawns, what is the best combination of hours of painting and mowing (he wants to make the most money) for him to schedule each week? 1. The variables are: x is the y is the 2. Now write the four constraints. 3. Graph the constraints. Last class you found that the x- and y-intercepts were helpful. Find them first. You will need to shade the feasible region. Often the origin can be used as the test point. Write down your four test points and determine if its coordinates satisfy ALL constraints. There is only one region, the feasible region, for which that will happen. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 29 of 58 Unit 8, Culminating Experience 2 Activity 1.4a, p. 2 of 3 4. Find the coordinates of the corner points. Some will be intercepts of the constraint lines. For one corner you will need to solve a system of equations. Show your work here. 5. Write down your objective function. 6. Now make a table of values for the corner points and select the corner that gives you a maximum. x y CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Profit = Page 30 of 58 Unit 8, Culminating Experience 2 Activity 1.4a, p. 3 of 3 7. Write down the solution after you have checked to be sure it does make sense. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 31 of 58 Unit 8, Culminating Experience 2 Activity 1.4b, p. 1 of 3 Suggested Research Question List Name: ______________________________________ Date: _____________________ 1. Research how linear programming came to being. How did it get its name? What role did World War II and computers play in its development? 2. Have there been any recent developments in the field of linear programming, sometimes called Operations Research (OR)? How, if at all, does linear programming or OR affect our daily life and how we live? 3. Joseph Fourier proved the Linear Programming Theorem in 1826. It states: If a feasible region in a linear programming problem is convex and bounded, then the maximum or minimum quantity for the linear objective function is determined at one (or more) of the vertices of the region. Like many mathematical discoveries and proofs, it waited many years before being widely used, in this case more than 100 years. Who is Fourier? What is his role in the field of mathematics? 4. In 1947 George Danzig, Leonld Hurwitz and T. C Koopmans invented the simplex algorithm or method used for solving “big” linear programming problems. President Gerald Ford in 1975 gave George Danzig a Presidential Award for his contribution. Koopmans received a Nobel Prize in 1982. Research the lives of these men and their contribution to the simplex method. 5. In 1947 John von Neumann developed the theory of the duality. Who is von Neumann and what is meant by the duality? Demonstrate its usefulness. ( For students needing challenge) 6. Study the simplex method and solve a small linear programming problem using it. ( For students needing challenge) 7. In 1945, George Stiegler worked on the problem of determining a least expensive, yet healthy diet. He received a Nobel Prize for his work. Find out more about what he did and his diet. 8. In 1979 the Soviet mathematician L. G. Kachian developed the ellipsoid method, which has not proved as useful as the simplex method, but it is noteworthy in this developing field of Operations Research. Research Kachian and his contributions. 9. In 1984, 29-year old Neredra Karmarkar of ATT Bell Laboratory announced his algorithm. Is it better than the simplex method? Research Karmarkar and the state of his linear programming algorithm. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 32 of 58 Unit 8, Culminating Experience 2 Activity 1.4b, p. 2 of 3 Student can research large linear programming problems. See below for some sources Large Scale Linear Programming Application Areas Problem areas where large linear programming problems arise are: Pacific Basin facility planning for AT&T The problem is to determine where undersea cables and satellite circuits should be installed, when they will be needed, the number of circuits needed, cable technology, call routing, etc over a 19 year planning horizon (an linear programming with 28,000 constraints, 77,000 variables). Military officer personnel planning The problem is to plan US Army officer promotions (to Lieutenant, Captain, Major, Lieutenant Colonel and Colonel), taking into account the people entering and leaving the Army and training requirements by skill categories to meet the overall Army force structure requirements (an linear programming with 21,000 constraints and 43,000 variables). Military patient evacuation The US Air Force Military Airlift Command (MAC) has a patient evacuation problem that can be modeled as a linear programming problem. They use this model to determine the flow of patients moved by air from an area of conflict to bases and hospitals in the continental United States. The objective is to minimize the time that patients are in the air transport system. The constraints are: All patients that need transporting must be transported; and Limits on the size and composition of hospitals, staging areas and air fleet must be observed. 1. 2. MAC have generated a series of problems based on the number of time periods (days). A 50 day problem consists of an linear programming with 79,000 constraints and 267,000 variables (solved in 10 hours). Military logistics planning The US Department of Defense Joint Chiefs of Staff have a logistics planning problem that models the feasibility of supporting military operations during a crisis. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 33 of 58 Unit 8, Culminating Experience 2 Activity 1.4b, p. 3 of 3 The problem is to determine if different materials (called movement requirements) can be transported overseas within strict time windows. The linear programming includes capacities at embarkation and debarkation ports, capacities of the various aircraft and ships that carry the movement requirements and penalties for missing delivery dates. One problem (using simulated data) that has been solved had 15 time periods, 12 ports of embarkation, 7 ports of debarkation and 9 different types of vehicle for 20,000 movement requirements. This resulted in an linear programming with 20,500 constraints and 520,000 variables (solved in 75 minutes). Source: http://people.brunel.ac.uk/~mastjjb/jeb/or/solvelp.html CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 34 of 58 Unit 8, Culminating Experience 2 Activity Rubric 1.4c, p. 1 of 3 Linear Programming Research Presentation Rubric Component 0 = Missing 1. The research question or topic is clearly identified. Students fail to identify a research question/topic during the presentation. 2. Insightful information is provided based on the research. Students provide no information relevant to the research question or topic. 3. Appropriate and informative graphics/visual aids are included to enhance the presentation. The group does not provide visual aids. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 1 = Needs Improvement Students define a research topic or question, but the question is not “interesting” or relevant. 2 = Proficient Students define the research question or topic, but it is not communicated clearly or comes too late in the presentation. Students provide a Students provide a very limited quantity reasonable quantity of research about of research, but their topic or only a limited question. amount of insightful information about their topic or question. The group shares The group shares visual aids during visual aids during the presentation, but the presentation the information that are clearly seen cannot be easily seen by the audience. by the audience. Or, However, the aids do not provide number is limited relevant information. or only some Page 35 of 58 3 =Advanced Students clearly define the research question or topic early in the presentation. Students provide a sufficient quantity of research, most or all of which is insightful, informative and relevant. The group shares numerous visual aids that enhance the presentation with relevant and interesting information. Student SelfReflection Pts. Earned Component 0 = Missing 1 = Needs Improvement 4. Teamwork is demonstrated during the presentation. Only one member of the group presents the solution. One team member dominates presentation while others play minor roles. 5. Presentation follows a logical sequence and conclusion. A logical or progressive sequence is completely absent. The presentation jumps around, showing a lack of organization. 2 = Proficient provide relevant information. Most team members have an important part of the presentation, but one team member plays a very minor role. The presentation is organized, but some topics are presented out or order. Or, a conclusion is not clearly stated. 6. Students answer Students are related questions, unable to address showing a strong questions. understanding of the topic. Students attempt to answer questions, but they show a very poor understanding of the research. Students are able to answer questions, but responses are not as insightful as would be expected following intense research on their topic. 7. The written report clearly captures the essence of the The written report omits key components of the oral presentation The written report follows the sequence of the oral presentation, but it Students submit no written report to accompany the oral presentation. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 36 of 58 3 =Advanced All team members have an important role in the presentation of the project. The presentation is well organized, presented in a logical sequence, and has a clearly defined conclusion. Students answer questions showing a strong understanding of the research on their topic. The written report follows the sequence of the oral presentation Student SelfReflection Pts. Earned Component 0 = Missing oral presentation. 8. The written report cites three or more resources in sufficient detail. Resources are not cited. 1 = Needs Improvement and/or does not follow the sequence of the presentation. Only one or two resources are cited. 2 = Proficient Student SelfReflection Pts. Earned omits a key and includes a component of the detailed account oral presentation or consistent with all fails to fully collate components of the all material. presentation. Three or more Three or more resources are cited, resources are cited but not in sufficient in sufficient detail. detail. For No important example, internet references are links do not lead to omitted. the precise webpage that contains the information cited. Total Points Earned = _____ out of 24 possible points = ______ Comments: CT Algebra One for All Unit 8, Culminating Experience 8 13 09 3 =Advanced Page 37 of 58 Unit 8: Investigation 1 Activity 1.5a, p. 1 of 3 The Farmer Name: ____________________________ Date: _________________________ A Connecticut farmer grows corn and apples on his farm. He ships both items in the same size box and his truck can carry at most 500 boxes per trip. Past records indicate that each shipment should contain at least 100 boxes of each product. Also, the number of boxes of apples should not exceed the number of boxes of corn. If this Connecticut farmer receives a profit of $6 for each box of apples and $4 for each box of corn, how many boxes of each should he load on his truck to maximize his profit? 1. The variables are: x is the y is the 2. Now write the 4 constraints. 3. Graph the inequalities. Shade the feasible region. Write down your test points and determine if the coordinates of each satisfy all constraints. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 38 of 58 Unit 8, Investigation 1 Activity 1.5a, p. 2 of 3 4. Find the coordinates of the corner points. Show your work here. 5. Write down your objective function. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 39 of 58 Unit 8, Investigation 1 Activity 1.5a, p. 3 of 3 6. Now make a table of values for the corner points and select the corner that gives you a maximum. x y Profit = 7. Write down the solution after you have checked to be sure it does make sense. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 40 of 58 Unit 8, Investigation 1 Activity 1.5b, p. 1 of 2 Supplemental Linear Programming Problems 1. A local artist working at the town fair makes caricatures and portraits. The caricatures cost $4 to make while the portraits cost $10 to produce. It takes 10 minutes to make a caricature and 30 minutes to make a portrait. The artist has $500 for supplies and a total of 22.5 hours at the fair. She would like to charge $10 for a caricature and $20 for a portrait. She is going to donate all proceeds of the weekend fair to a local charity. What number of each type of work should she make in order to maximize the donation for the charity? 2. At the TI Activities Exchange http://education.ti.com/educationportal/activityexchange/Activity.do?aId=8272&c id=US. “Design a Better Drink Can” can be used for students who may be having trouble coming up with their own linear programming problem to research or as an additional classroom problem because it relates geometry and algebra. Activity is designed to come up with optimal dimensions for different can sizes. It explores the relationships between dimensions of a can, its volume and its surface area. 3. At http://illuminations.nctm.org under grade 9 – 12 algebra select “Dirt Bike Dilemma”. You may just use the problem or parts of the lesson and activity sheets. 4. A student is making two types of wallets out of duct tape. She is going to make a tri-fold wallet and a bi-fold wallet. The tri-fold wallet takes 1 hour to finish and the bi-fold wallet takes ½ hour to finish. The tri-fold wallet costs $1 of duct tape to make and the bi-fold costs $0.75 of duct tape to make. The tri-fold wallet costs $10 and the bi-fold wallet cost $8. If the student has $24 to purchase tape and 20 hours throughout the week to make wallets, what combination of tri-fold and bifold wallets should she make to maximize profit? 5. For Valentine’s Day the student council is going to sell single roses and chocolate hearts. The council must first buy roses and hearts to sell. Each rose costs $0.75 while each chocolate heart costs $0.50. The council has at most $270 to spend on this fundraiser. On average each rose takes 2 minutes to wrap with a red ribbon and write the student’s name on a card and the chocolate heart takes about one minute to write the student’s name on a card. The student council has at most 10 hours to wrap the ribbons and write student’s names on cards. If the student council will make a profit of $0.75 on each rose arrangement and $0.50 on each chocolate heart, what combination of roses and chocolate hearts should they try to sell? CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 41 of 58 Unit 8, Investigation 1 Activity 1.5b, p. 2 of 2 6. Numb3rs Season 3 “The Mole - Branch and Bound” provided on the Activities Exchange at http://education.ti.com/educationportal/activityexchange/Activity.do?cid=US&aId =7508. This problem is designed to answer how linear programming can be used to find the most probable outcome of a situation. It will study the branching and bounding algorithm that can be used when integer solutions are desired but not obtained. It is written for Algebra 1 students. 7. Bakers Choice published by Key Curriculum Press has a real life problem involving a Bakery that wants to maximize their profits. It is a supplemental module for Interactive Mathematics. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 42 of 58 Unit 8: Investigation 1: Activity 1.6a, p. 1 of 5 Farm Subsidies Name: ________________________________ Date: _________________________ Farming can be a very difficult way of life, as sometimes “Mother Nature” does not cooperate. A drought can wipe out entire crops. A spring season with too much rain can delay planting and make it difficult for seeds to sprout before they rot. On occasion, insects can damage entire fields of crops. Without healthy crops, there is nothing for the farmer to sell and therefore very little income in those difficult years. Without help, many farmers would sell their land and find another job. But, our country needs the farmers and the crops they grow. As a result, the US government helps our nation’s farmers by providing them with subsidies. A subsidy is extra money paid directly to the farmers to help them and their families earn enough money to be able to live comfortably and continue farming, especially in those difficult years. If the farmer accepts a subsidy, the government determines which crops are needed and then tells the farmer what to grow on his or her land. The farmer must follow these instructions to receive the subsidy. A farmer does not have to accept a subsidy. He or she may try to earn a living without the government’s help. Some farmers feel they can earn more money by making their own decisions. Others do not like to take directions from the government. Suppose a farmer is trying to decide whether or not to accept a subsidy from the government. Based on the following questions, how does getting a subsidy affect this one farmer’s decision on what to plant and how much? A1. Suppose a farmer has 200 acres of land on which the family can plant any combination of corn and oats. Each acre of corn that is planted requires 2 workerdays of labor and costs the farmer $10. Each acre of oats that is planted requires ½ worker-day of labor and costs the farmer $5. Suppose the farmer gets $30 in revenue for each acre of corn planted and $20 in revenue for each acre of oats planted. If the farmer has $1,100 to spend on planting and 160 worker-days of labor available for the year, how many acres of corn and how many of oats should the farmer plant to maximize his revenue? A2. A corn subsidy is available and increases the corn revenue from $30 to $50 per acre. Since the farmer had planned on planting corn anyway, he is considering taking the subsidy. If he takes the subsidy, should the farmer change the number of acres he plants with corn? If so, how many acres should he now plant with corn and what will be his new maximum revenue? CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 43 of 58 Unit 8, Investigation 1 Activity 1.6a: p. 2 of 5 Part A1 1. The variables are: x is the y is the 2. Now write the 3 constraints in addition to the non negativity constraints. 3. Graph and shade the feasible region. Write down your test points and determine if the coordinates of each satisfy all the constraints. There is only one region for which that will happen. Your teacher will give you a separate piece of graph paper. 4. Find the coordinates of the corner points. Show your work here. 5. Write down your objective function. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 44 of 58 Unit 8, Investigation 1 Activity 1.6a, p. 3 of 5 6. Now make a table of values for the corner points and select the corner that gives you a maximum. x y Revenue = 7. Write down the solution after you have checked to be sure it does make sense. Part A2 8. Write down your new objective function. 9. Now make a table of values for the corner points (the corner points have not changed) and select the corner that gives you a maximum. x y CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Revenue = Page 45 of 58 Unit 8, Investigation 1 Activity 1.6a, p. 4 of 5 10. Write down the solution after you have checked to be sure it does make sense. Do you think the farmer should accept the subsidy? Explain. Part B Instead suppose the subsidy increases the corn revenue from $30 to $40 for an acre of corn. How will this affect the decision on planting? 11. Write down your new objective function. 12. Now make a table of values for the corner points (the corner points have not changed) and select the corner that gives you a maximum. x y CT Algebra One for All Unit 8, Culminating Experience 8 13 09 revenue = Page 46 of 58 Unit 8, Investigation 1 Activity 1.6a, p. 5 of 5 13. Write down the solution (something should be different here) after you have checked to be sure it does make sense. Make sure you answered the question that was posed in part B. 14. Write a summary paragraph about how subsidies might affect this farmer’s decisions. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 47 of 58 Unit 8: Investigation 1 Activity 1.6b, p. 1 of 1 Natasha’s Cat Name: ___________________________________ Date: _________________________ Use your linear programming algorithm to solve the problem below. The seven steps are repeated here for your convenience. 1. Clearly define each variable to be used in the constraints. 2. Define all constraints. Recall that many real world problems must include the constraints of x > 0 and y > 0. 3. Graph the system of inequalities and shade the feasible region. 4. On the graph, determine and label the corner points with their coordinates. 5. Define the objective function 6. Now evaluate the objective function f = ax + by at all corner points. Make a table or use the table feature of your grapher. What is the maximum or minimum value? 7. Step back and make sure your solution makes sense. Then state your solution and make sure to use appropriate units. Natasha’s cat, Dancer, will eat both dry food and wet (canned) food. Natasha wants Dancer to eat meals that are nutritious, but would also like to save some money on her cat’s food bill. Dancer usually eats wet food. However, the wet food is more expensive. In order to save money, Natasha is trying to decide if she can switch her cat to a diet with some wet and some dry food, or perhaps all dry food. However, she still wants to meet the nutritional requirements of her cat. Protein and fat are two important components of a cat’s diet. Proteins serve as building blocks for bones and muscles, while fat provides energy and helps with the absorption of vitamins. Dancer needs at least 60 grams of protein per day and at least 12 grams of fat per day. The wet food provides about 10 grams of protein per serving while the dry food provides about 30 grams of protein per serving. Both the wet and dry food contain about 4 gram of fat per serving. The wet food costs 80 cents per serving and the dry food costs 66 cents per serving. How many servings of wet and dry food will Dancer need each day to meet her nutritional requirements while keeping Natasha’s pet food bill a minimum? CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 48 of 58 Unit 8, Investigation 1 Activity 1.7a, P. 1 of 1 Create Your Own Linear Programming Problem Name: _______________________________________ Date: ____________________ Here are some ideas to follow: 1. The oil industry uses linear programming to maximize their profit. Research the use of linear programming within the oil industry and how it has improved their profits. How did they make decisions before linear programming was developed? How do they use it in their product and distribution? 2. In a group, members will construct a company which makes two different products. Members will build realistic constraints for their products and assign a profit or cost to their products. Once the question has been developed, it should be solved and presented to the class. 3. Telephone companies have to schedule millions and millions of phone calls each day. How is linear programming incorporated into their delivery system? How does this affect their product costs and profits? 4. UPS and FedEx must ship millions of packages a day, all over the world. How do they incorporate linear programming into their shipping schedules? How are computer models developed and implemented? How has the development of different technologies aided in their success or failures? 5. A local tire company may be contacted to determine what the manufacturing costs are for two or three different tires, and the profit and the time needed to produce a specific tire. 6. A local restaurant can be contacted to determine how menu items are selected and how they set their prices. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 49 of 58 Unit 8, Investigation 1 Activity 1.7b, p. 1 of 4 Rubric for Create Your Own Problem Component 0 = Missing 1. Definition of variables Students do not define the variables. 1 = Needs Improvement Students define variables, but one or more is incorrect. 2. Construction of problem constraints Students do not construct constraints. Students construct constraints, but one or more is incorrect. 3. Graph of feasible region Students do not provide a graph. Students provide a graph, but lines do not match equations or lines appear correct but none of the following are shown: Labeled axes and correct scale Clearly labeled intercepts Correct region shaded CT Algebra One for All Unit 8, Culminating Experience 8 13 09 2 = Proficient 3 =Advanced Students define variables correctly but do not use clear statements. Students construct constraints correctly but do not list the nonnegativity constraints. Students provide a graph with correctly drawn lines. However, one or two of the following is missing: Labeled axes and correct scale Clearly labeled intercepts Correct region shaded Students define variables correctly and clearly. Page 50 of 58 Students construct constraints correctly, including the nonnegativity constraints. Students provide a graph and define the feasible region correctly and all three bulleted items are included: Labeled axes and correct scale Clearly labeled intercepts Correct region shaded Student SelfReflection Pts. Earned Component 0 = Missing 4. Identification of the objective function Students do not identify an objective function. 5. Calculation of the intersection point of the boundary lines Students do not identify the intersection point of the boundary lines of the nontrivial constraints. 6. Evaluation of the objective function at each vertex and identification of the optimal solution Students do not evaluate objective function at the vertices. 7. Contextual understanding of solution. Students do not Students present an attempt to put the incorrect solution in context. interpretation of each of the coordinates of the optimal solution in context, or omit one coordinate. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 1 = Needs Improvement Students define an objective function, but are optimizing the wrong quantity. Students list an incorrect ordered pair for the intersection of the non-trivial constraints and show little, if any, algebraic work. Students evaluate the objective function at the vertices, but half or more of the calculations are incorrect or missing. 2 = Proficient 3 =Advanced Students define an objective function, but use incorrect coefficients or reverse coefficients of x and y. Students identify the correct point of intersection for the non-trivial constraints but show insufficient algebraic justification. Students evaluate the objective function at the vertices, and the majority of the outputs are correct. Students identify the optimal solution based on their calculations. Students define a correct and appropriate objective function. Students correctly identify one of the coordinates in the optimal solution in context, but err in the interpretation of the other. Students present correct understanding of optimal solution in context. Page 51 of 58 Students identify the correct point of intersection for the non-trivial constraints and show a complete algebraic justification. Students evaluate the objective function correctly at each of the vertices and clearly identify the optimal solution. Student SelfReflection Pts. Earned Component 0 = Missing 8. Quality of the created problem: Students create an interesting and relevant problem with reasonable constraints and optimal solution in context. 9. Teamwork The problem is not coherent. Only one member of the group presents the solution. One team member dominates the presentation while others play minor roles. 10. Visual display Group does not provide visual aids. Group shares graphs and tables during the presentation, but the information cannot be easily seen by the audience. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 1 = Needs Improvement The problem is little more than a clone of a prior problem in the unit. 2 = Proficient 3 =Advanced The problem is interesting and relevant. However, the constraint equation and/or optimal solution do not provide reasonable values in context. The problem is interesting and relevant. The constraint equations and optimal solution are reasonable in the context. Most team members have an important part of the presentation, but one team member plays a very minor role. Group shares graphs and tables during the presentation that are clearly seen by the audience. All team members have an important role in the presentation of the project. Student SelfReflection Pts. Earned Group shares graphs and tables and at least one other creative visual aid that enhance the presentation. Total Points Earned = ______ out of 30 possible points = ______ Page 52 of 58 UNIT 8 LINEAR PROGRAMMING – CULMINATING PROBLEM PART A Name: _______________________________________________ Date: ________________ Jewelry Business 1 Hector is starting his own business making jewelry for a large discount store. Long-term projections indicate an expected demand of at least 100 pairs of silver hoop earrings and 80 beaded bracelets a week. Because of limitations on production capacity, no more than 200 hoop earrings and 170 beaded bracelets can be made weekly. To satisfy the contract, a total of at least 200 pieces of jewelry must be shipped each week. If each pair of hoop earrings sells at a $2.00 loss, but each beaded bracelet produces a $5.00 profit, how many of each type should he make weekly to maximize net profit? a. Choose your variables: x= y= b. Write inequalities for the constraints on the variables. c. Write an equation of the Objective Function. PLEASE GIVE YOUR TEACHER THIS SHEET. YOUR TEACHER WILL GIVE YOU PART B OF THE TEST. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 53 of 58 UNIT 8 LINEAR PROGRAMMING TEST – CULMINATING PROBLEM PART B Name: ___________________________________________ Date: ______________ Jewelry Business 1. Hector is starting his own business making jewelry for a large discount store. Long-term projections indicate an expected demand of at least 100 pairs of silver loop earrings and 80 beaded bracelets a week. Because of limitations on production capacity, no more than 200 hoop earrings and 170 beaded bracelets can be made weekly. To satisfy the contract, a total of at least 200 pieces of jewelry must be shipped each week. If each pair of hoop earrings sells at a $2.00 loss, but each beaded bracelet produces a $5.00 profit, how many of each type should he make weekly to maximize net profit? The constraints for the variables are: 100 x 200 80 y 170 x y 200 The Objective Function is: P = -2x + 5y Use the constraints and objective function above to complete the problem. a. Use your calculator to graph the constraint inequalities. b. Use the grid below to draw your graph and indicate the feasible region. Label your graph and indicate scales on your axes. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 54 of 58 c. Use your calculator to determine the corner points (vertices) of the feasible region. d. For each corner point, determine the value of the Objective Function. Show your work. e. Explain how you determined the number of silver hoop earrings and beaded bracelets to make to maximize your profit. Is the profit reasonable for Hector to start his business? CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 55 of 58 UNIT 8 LINEAR PROGRAMMING TEST – CULMINATING PROBLEM PART A Name: ___________________________________________ Date: ______________ Greenhouse Business 1 Marlene builds greenhouses. Her greenhouses are popular because many people are interested in growing their own vegetables. She uses ten small glass panes and fifteen large glass panes for small greenhouses. She uses fifteen small glass panes and forty-five large glass panes for a large greenhouse. She has available sixty small glass panes and one hundred thirty-five large glass panes. If Marlene makes $390 profit on a small greenhouse and $520 on a large greenhouse, how many of each type should she build to maximize profit? a. Choose your variables: a. x = b. y = b. Write inequalities for the constraints on the variables. c. Write an equation of the Objective Function. PLEASE GIVE YOUR TEACHER THIS SHEET. YOUR TEACHER WILL GIVE YOU PART B OF THE TEST. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 56 of 58 UNIT 8 LINEAR PROGRAMMING TEST – CULMINATING PROBLEM PART B Name: ___________________________________________ Date: ______________ Greenhouse Business 1. Marlene builds greenhouses. Her greenhouses are popular because many people are interested in growing their own vegetables. She uses ten small glass panes and fifteen large glass panes for small greenhouses. She uses fifteen small glass panes and forty-five large glass panes for a large greenhouse. She has available sixty small glass panes and one hundred thirty-five large glass panes. If Marlene makes a $390 profit on a small greenhouse and $520 on a large greenhouse, how many of each type should she build to maximize profit? The constraints for the variables are: x0 y0 10x + 15y 60 15x + 45y 135 The Objective Function is: P = 390x + 520y Use the constraints and objective function above to complete the problem. a. Use your calculator to graph the constraint inequalities. b. Use the grid below to draw your graph and indicate the feasible region. Label your graph and indicate scales on your axes. CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 57 of 58 c. Use your calculator to determine the corner points (vertices) of the feasible region. d. For each corner point, determine the value of the Objective Function. Show your work. e. Explain how you determined the number of small greenhouses and large greenhouse to maximize your profit. Is the profit reasonable for Marlene’s business? CT Algebra One for All Unit 8, Culminating Experience 8 13 09 Page 58 of 58