Instructions: Answer each question. Use Lindo to solve all problems. Show all work by describing variables,


Instructions: Answer each question. Use Lindo to solve all problems. Show all work by describing variables, stating assumptions, illustrating model and showing output solution to the problem. The exam work should be completed in a word file and must be downloaded by the due date. You must also upload answers to the excel answer template

  1. Costal States (15 points)

Costal States produces eight (8) chemical products that are sold to companies in various industries. Information about the products that Costal States provides on a daily basis is shown in the table below. This table shows profit margin for each product, capacity at each plant for producing the product and the consumption of natural gas required to produce each product. Additionally, the table shows the maximum production rate percentage that can be ascertained for each product on a daily basis. This maximum production rate for each product takes into account market demand requirements for each product and potential system losses in the production process. Note, that Costal States produces only one product (Ammonium Nitrate) to it’s maximum production rate, no other product is be produced at its full capacity rate.

An important ingredient to the production process is natural gas as this provides the heating for the furnaces in the production of each chemical product. The amount of natural gas required for each product is also detailed in the table

PRODUCT Profit
(Dollars per Ton)
Capacity
(Tons Per Day)
Maximum Production Rate
(% of Capacity)
Natural Gas Consumption
(1,000 cubic feet per ton)
PHOSPHORIC ACID $60 400 80 5.5
UREA $80 250 80 7.0
AMMONIUM PHOSPHATE $90 300 90 8.0
AMMONIUM NITRATE $100 300 100 10.0
CHLORINE $50 800 60 15.0
CAUSTIC SODA $50 1,000 60 16.0
VINYL CHLORIDE MONOMER $65 500 60 12.0
HYDROFLUORIC ACID $70 400 80 11.0

Costal States receives 36,000,000 cubic feet of natural gas per day from Cajun Pipelines. Recently, Cajun Pipelines has informed Costal States that it may see a reduction in natural gas supply by either 20% or 40% in the pursuing winter months. This curtailment is the result of government energy regulations. Use Linear Programming (not integer) to determine the following:

  1. What is Costal States maximum profit with no curtailment in the natural gas resource
  2. What is the impact to maximum profit and chemical production with a 20% curtailment of natural gas resource
  3. What is the impact to maximum profit and chemical production with a 40% curtailment of natural gas resource
  4. Suppose there is a 40% curtailment in natural gas resource. How much would Costal be willing to pay for additional gas resources (Assume Costal States is only looking to break even (no additional profits) and how much resources would they purchase at this price (answer this from the confines of sensitivity analysis for the model)
  1. Coffee Blends ( 20 points )
    Ms. Olsen, a coffee processor, markets three blends of coffee. They are Brand X, Minim and Taster's Reject. Ms. Olsen uses two types of coffee beans, Columbian and Mexican, in her coffee. The following chart lists the compositions of the blends.
    Blend Columbian Beans Mexican Beans
    Brand X 80% 20%
    Minim 50% 50%
    Taster’s Reject 30% 70%

    Ms. Olsen HAS purchased 20,000 pounds of Columbian beans at 90 cents per pound, and she has purchased 30,000 pounds of Mexican beans at 50 cents per pound. The beans have been delivered and are within the warehouse ready to use for coffee production. Unused Columbian beans can be sold at cost to another processor, but unused Mexican beans can be sold only for 55 cents per pound. Due to warehouse space limitations, Ms. Olsen must dispose of all unused beans.
    Brand X sells for $2.60 per pound, Minim sells for $2.50 per pound, and Taster's Reject brings $2.34 per pound. All three products have the same production and packaging costs of $1.60 per pound.
    Ms. Olsen is interested in finding the production schedule that will maximize profit.
    Formulate a relevant linear programming model for this problem and determine the solution that maximizes profit (sales –cost)
  2. Giant Motor Company II (30 points)
    This problem deals with strategic planning issues for a large company. The main issue is planning the company’s production capacity for the conning year. At issue is the overall level of capacity and the type of capacity - for example, the degree of flexibility in the manufacturing system. You are to use mixed integer programming and zero one programming to solve this problem
    Problem Statement :
    Giant Motor Company (GMC) produces three lines of cars for the domestic (U.S.) market: Lyras, Libras and Hydras. The Lyra is a relatively inexpensive subcompact car that appeals mainly to first-time car owners and to households using it as a second car for commuting. The Libra is a sporty compact car that is sleeker, faster, and roomier than the Lyra. Without any options, the Libra costs slightly more than the the Lyra. Additional options increase the price further. The Hydra is the luxury car of the GMC line. It is significantly more expensive than the Lyra and Libra, and it has the highest profit margin of the three cars.
    Retooling Options for Capacity Expansion
    Currently, GMC has three manufacturing plants in the US. Each plant is dedicated to producing a single line of cars. In its planning for the coming year, GMC is considering the retooling of its Lyra and/or Libra plants. Retooling either plant would represent a major expense for the company. The retooled plants would have significantly increased production capacities. Although having greater fixed costs , the retooled plants would be more efficient and have lower marginal production costs-that is, higher marginal profit contributions, In addition, the retooled plants would be flexible- they would have the capability of producing more than one line of cars.
    The characteristics of the current plants and the retooled plants are given in table 1. The retooled Lyra and Libra plants are prefaced by the word new . The fixed costs and capacities in Table 1 are given on an annual basis. A dash in the profit margin section indicates that the plant cannot manufacture that line of car. For example, the new Lyra plant would be capable of producing both Lyras and Libras but not Hydras. The new Libra plant would be capable of producing any of the three lines of cars. Note, however, that the new Libra plant has a slightly lower profit margin for producing Hydras than the Hydra plant. The flexible new Libra plant is capable of producing the luxury Hydra model but is not quite as efficient as the current Hydra plant that is dedicated to Hvdra production.
    The fixed costs are annual costs that are incurred by GMC independent of the number of cars that are produced by the plant. For the current plant configurations, the fixed costs include property taxes, insurance, payments on the loan that was taken out to construct the plant, and so on. If a plant is retooled, the fixed costs will include the previous fixed costs plus the additional cost of the renovation. The additional renovation cost will be an annual cost representing the cost of the renovation amortized over a long period.
    Table 1 – Plant Characteristics
    Lyra Plant Libra Plant Hydra Plant New Lyra Plant New Libra Plant
    Capacity (in 1000s) 900 800 900 1600 1800
    Fixed Cost (in $millions) 2000 2000 2600 3400 3700

    Profit Margin by Car line (in $1000s)
    Lyra Plant Libra Plant Hydra Plant New Lyra Plant New Libra Plant
    Lyra 2 - - 2.5 2.3
    Libra - 3 - 3.0 3.5
    Hydra - - 5 - 4.8

    Demand for GMC Cars
    Short-term demand forecasts have been very reliable in the past and are expected to be reliable in the future. Longer-term forecasts are not so accurate. The, demand for GMC cars for the coming year is given in Table 2.
    Table 2 Demand for GMC Cars
    Demand
    (in 1000s)
    Lyra 1400
    Libra 2100
    Hydra 800

    A quick comparison of plant capacities and demands in Tables 1 and 2 indicates that GMC is faced with insufficient capacity. Partially offsetting the lack of capacity is the phenomenon of demand diversion. If a potential car buyer walks into a GMC dealer showroom wanting to buy a Lyra but the dealer is out of stock, frequently the salesperson can convince the customer to purchase the better Libra car, which is in stock. Unsatisfied demand for the Lyra is said to be diverted to the Libra. Only rarely in this situation can the salesperson convince the customer to switch to the luxury Hydra model.
    From past experience GMC estimates that 30% of unsatisfied demand for Lyras is diverted to demand for Libras and 5% to demand for Hydras. Similarly, 10% of unsatisfied demand for' Libras is diverted to demand for Hydras. For example, if the demand for Lyras is 1,400,000 cars, then the unsatisfied demand will be 500,000 if no capacity is added. Out of this unsatisfied demand, 150,000 (=500,000 x .3) will materialize as demand for Libras, and 25,000 (= 500,000 x .05) will materialize as demand for Hydras. Similarly, if the demand for Libras is 1,220,000 cars (1,100,000 original demand plus 120,000 demand diverted from Lyras), then the unsatisfied demand for Lyras would be 420,000 if no capacity is added. Out of this unsatisfied demand, 42,000 (= 420, 000 x . 1) will materialize as demand for Hydras. All other unsatisfied demand is lost to competitors. The pattern of demand diversion is summarized in Table 3
    Table 3 – Demand Diversion Matrix
    Lyra Libra Hydra
    Lyra N/A 0.3 .05
    Libra 0 N/A .10
    Hydra 0 0 N/A

    Ouestion:
    GMC wants to decide whether or not to retool the Lyra and Libra plants. In addition, GMC wants to determine its production plan at each plant in the coming year. Based on the previous data, formulate a mixed integer programming model for solving GMC's production planning-capacity expansion problem for the coming year.
  3. Market Research ( 20 Points)

A market research firm has been retained to conduct focus group interviews for a real estate company. Plans are made to classify participants to age: over 45 or 45 and under and as to wether or not they have recently bought and/or sold a house (within the last two years). Specific guidelines have been developed:

  • At least 100 people must be selected
  • At least 75% of the participants must have bought or sold a house recently
  • Of those who have not bought or sold recently, at least 40% must be over 45 years of age
  • No more than 40% of participants should be 45 or under

There are preliminary screenings with associated costs. The cost for each participant begins at $10. Additional contact with those over 45 raises the cost by $12. Additional time with the recent buyers and sellers adds $7 to the cost of including those participants. Formulate a linear programming model to determine the amount of and type of participants that minimizes total cost

  1. First West Chemical ( 20 Points )

First West Chemical Company produces two chemical ingredients for pharmaceutical firms; formula X and formula Y. Production of each ingredient requires two processes. A unit of Formula X requires 4 hours in process 1 and 3 hours in process 2. A unit in formula Y requires 2 hours in process 1 and 5 hours in process 2. The normal operating production times for the two processes are as follows: process 1, 70 hours and process 2, 60 hours. The production process of formula X results in one unit of a by-product called XZ. Four (4) units of X produce 1 unit of XZ. The production process for formula Y yields 5 units of a by-product, YK for each unit of formula Y. The unit profits for formulas X and Yare $10,000 and $15,000 respectively. By products XZ yields $6000 unit profit. By product YK yields a $3000 unit profit for up to 15 units. Because of the limited market and the danger involved in handling the material, any by product YK in excess of 15 units must be destroyed at a unit cost of $4,000. Also due to storage regulations, no more than 15 units of Formula X can be produced.

The management at this chemical company has established the following goals in order of importance:

  1. Avoid any underutilization of normal operation hours of each of the two processes. Each of equal importance.
  2. Meet the outstanding orders for 8 units of formula X and 7 units of Formula Y. Each of equal importance.
  3. Limit any overtime operation of each of the two production process to 10 hours. Each of equal importance.
  4. Achieve a profit goal of $220,000
  5. Limit the production of by-product YK to 15 units.
  6. Minimize the overtime operation of the production processes. Each of equal importance.

Formulate this problem into a mathematical model and determine the solution that best satisfies these goals.

Price: $48.52
Solution: The downloadable solution consists of 24 pages, 2452 words and 9 charts.
Deliverable: Word Document


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