Exam 4: Sensitivity Analysis and the Simplex Method

arrow
  • Select Tags
search iconSearch Question
flashcardsStudy Flashcards
  • Select Tags

When automatically running multiple optimizations in Analytic Solver Platform,what spreadsheet function indicates which optimization is being run?

(Multiple Choice)
4.9/5
(34)

Exhibit 4.1 The following questions are based on the problem below and accompanying Analytic Solver Platform sensitivity report. Carlton construction is supplying building materials for a new mall construction project in Kansas.Their contract calls for a total of 250,000 tons of material to be delivered over a three-week period.Carlton's supply depot has access to three modes of transportation: a trucking fleet,railway delivery,and air cargo transport.Their contract calls for 120,000 tons delivered by the end of week one,80% of the total delivered by the end of week two,and the entire amount delivered by the end of week three.Contracts in place with the transportation companies call for at least 45% of the total delivered be delivered by trucking,at least 40% of the total delivered be delivered by railway,and up to 15% of the total delivered be delivered by air cargo.Unfortunately,competing demands limit the availability of each mode of transportation each of the three weeks to the following levels all in thousands of tons): Week TruckingLimits Railway Limits Air Cargo Limits 1 45 60 15 2 50 55 10 3 55 45 5 Costs \ per 1000 tons) \ 200 \ 140 \ 400 The following is the LP model for this logistics problem. Let Xij = amount shipped by mode i in week j where i = 1Truck),2Rail),3Air)and j = 1,2,3 Let WLij = weekly limit of mode i in week j as provided in above table) 200X11 + X12 + X13)+ 140X21 + X22 + X23)+ 500X31 + MIN: X + X ) Subject to: 32 33 Xij ? WL ij for all i and j Weekly limits by mode X11 + X12 + X13 + X21 + X22 + X23 + X31 + X32 + X33 ? 250 Total at end of three weeks X11 + X21 + X31 + X12 + X22 + X32 ? 200 Total at end of two weeks X11 + X21 + X31 ? 120 Total at end of first week X11 + X12 + X13 ? 0.45*250 Truck mix requirement X21 + X22 + X23 ? 0.40*250 Rail mix requirement X31 + X32 + X33 ? 0.15*250 Air mix limit Xij ? 0 for all i and j Final Reduced Objective Allowable Allowable Value Cost Coefficient Increase Decrease Cell Name \ \ 6 Week 1 by Truck 45 0 200 360 1+30 \ \ 6 Week 1 by Rail 60 0 140 360 1+30 \ \ 6 Week 1 by Air 15 0 500 1+30 360 \ \ 7 Week 2 by Truck 50 0 200 0 1+30 \ \ 7 Week 2 by Rail 55 0 140 0 1+30 \ \ 7 Week 2 by Air 0 360 500 1+30 360 \ \ 8 Week 3 by Truck 13 0 200 1+30 0 \ \ 8 Week 3 by Rail 12 0 140 60 0 \ F\ 8 Week 3 by Air 0 360 500 1+30 360  Exhibit 4.1 The following questions are based on the problem below and accompanying Analytic Solver Platform sensitivity report. Carlton construction is supplying building materials for a new mall construction project in Kansas.Their contract calls for a total of 250,000 tons of material to be delivered over a three-week period.Carlton's supply depot has access to three modes of transportation: a trucking fleet,railway delivery,and air cargo transport.Their contract calls for 120,000 tons delivered by the end of week one,80% of the total delivered by the end of week two,and the entire amount delivered by the end of week three.Contracts in place with the transportation companies call for at least 45% of the total delivered be delivered by trucking,at least 40% of the total delivered be delivered by railway,and up to 15% of the total delivered be delivered by air cargo.Unfortunately,competing demands limit the availability of each mode of transportation each of the three weeks to the following levels all in thousands of tons):   \begin{array}{rrrr} \text { Week } & \text { TruckingLimits } & \text { Railway Limits } & \text { Air Cargo Limits } \\ \hline 1 & 45 & 60 & 15 \\ 2 & 50 & 55 & 10 \\ 3 & 55 & 45 & 5 \\ \hline \text { Costs } \$ \text { per } 1000 \text { tons) } & \$ 200 & \$ 140 & \$ 400 \end{array}   The following is the LP model for this logistics problem. Let <sup>X</sup><sub>ij </sub><sup>= amount shipped by mode i in week j</sup> where i = 1Truck),2Rail),3Air)and j = 1,2,3 <sub>Let</sub><sub> </sub>WL<sub>ij </sub>= weekly limit of mode i in week j as provided in above table) 200X<sub>11 </sub>+ X<sub>12 </sub>+ X<sub>13</sub>)+ 140X<sub>21 </sub>+ X<sub>22 </sub>+ X<sub>23</sub>)+ 500X<sub>31 </sub>+ MIN: X + X ) Subject to: 32 33 <sup>X</sup><sub>ij </sub><sup>? WL </sup><sub>ij </sub><sup>for all i and j</sup><sup> </sup>Weekly limits by mode X<sub>11 </sub>+ X<sub>12 </sub>+ X<sub>13 </sub>+ X<sub>21 </sub>+ X<sub>22 </sub>+ X<sub>23 </sub>+ X<sub>31 </sub>+ X<sub>32 </sub>+ X<sub>33 </sub>? 250 Total at end of three weeks <sup>X</sup><sub>11 </sub><sup>+ X</sup><sub>21 </sub><sup>+ X</sup><sub>31 </sub><sup>+ X</sup><sub>12 </sub><sup>+ X</sup><sub>22 </sub><sup>+ X</sup><sub>32 </sub><sup>? 200</sup><sup> </sup>Total at end of two weeks <sup>X</sup><sub>11 </sub><sup>+ X</sup><sub>21 </sub><sup>+ X</sup><sub>31 </sub><sup>? 120</sup><sup> </sup>Total at end of first week <sup>X</sup><sub>11 </sub><sup>+ X</sup><sub>12 </sub><sup>+ X</sup><sub>13 </sub><sup>? 0.45*250</sup><sup> </sup>Truck mix requirement <sup>X</sup><sub>21 </sub><sup>+ X</sup><sub>22 </sub><sup>+ X</sup><sub>23 </sub><sup>? 0.40*250</sup><sup> </sup>Rail mix requirement <sup>X</sup><sub>31 </sub><sup>+ X</sup><sub>32 </sub><sup>+ X</sup><sub>33 </sub><sup>? 0.15*250</sup><sup> </sup>Air mix limit X<sub>ij </sub>? 0 for all i and j   \begin{array}{rrrrrrr} &&\text { Final } & \text { Reduced } & \text { Objective } & \text { Allowable } & \text { Allowable } \\ &&\text { Value } & \text { Cost } & \text { Coefficient } & \text { Increase } & \text { Decrease }\\ \text { Cell } & \text { Name } & & & & \\ \hline \$ \mathrm{D} \$ 6 & \text { Week 1 by Truck } & 45 & 0 & 200 & 360 & 1 \mathrm{E}+30 \\ \$ \mathrm{E} \$ 6 & \text { Week 1 by Rail } & 60 & 0 & 140 & 360 & 1 \mathrm{E}+30 \\ \$ \mathrm{~F} \$ 6 & \text { Week 1 by Air } & 15 & 0 & 500 & 1 \mathrm{E}+30 & 360 \\ \$ \mathrm{D} \$ 7 & \text { Week 2 by Truck } & 50 & 0 & 200 & 0 & 1 \mathrm{E}+30 \\ \$ \mathrm{E} \$ 7 & \text { Week 2 by Rail } & 55 & 0 & 140 & 0 & 1 \mathrm{E}+30 \\ \$ \mathrm{~F} \$ 7 & \text { Week 2 by Air } & 0 & 360 & 500 & 1 \mathrm{E}+30 & 360 \\ \$ \mathrm{D} \$ 8 & \text { Week 3 by Truck } & 13 & 0 & 200 & 1 \mathrm{E}+30 & 0 \\ \$ \mathrm{E} \$ 8 & \text { Week 3 by Rail } & 12 & 0 & 140 & 60 & 0 \\ \$ F \$ 8 & \text { Week 3 by Air } & 0 & 360 & 500 & 1 \mathrm{E}+30 & 360 \end{array}     -Refer to Exhibit 4.1.Of the three percentage of effort constraints,Shipped by Truck,Shipped by Rail,and Shipped by Air,which should be examined for potential cost reduction? -Refer to Exhibit 4.1.Of the three percentage of effort constraints,Shipped by Truck,Shipped by Rail,and Shipped by Air,which should be examined for potential cost reduction?

(Essay)
5.0/5
(40)

The allowable increase for a changing cell decision variable)is

(Multiple Choice)
4.8/5
(39)

The Simplex method uses which of the following values to determine if the objective function value can be improved?

(Multiple Choice)
4.8/5
(32)

Exhibit 4.2 The following questions correspond to the problem below and associated Analytic Solver Platform sensitivity report. Robert Hope received a welcome surprise in this management science class;the instructor has decided to let each person define the percentage contribution to their grade for each of the graded instruments used in the class.These instruments were: homework,an individual project,a mid-term exam,and a final exam.Robert's grades on these instruments were 75,94,85,and 92,respectively.However,the instructor complicated Robert's task somewhat by adding the following stipulations: · homework can account for up to 25% of the grade,but must be at least 5% of the grade; · the project can account for up to 25% of the grade,but must be at least 5% of the grade; · the mid-term and final must each account for between 10% and 40% of the grade but cannot account for more than 70% of the grade when the percentages are combined;and · the project and final exam grades may not collectively constitute more than 50% of the grade.The following LP model allows Robert to maximize his numerical grade. Let W1 = weight assigned to homework W2 = weight assigned to the project W3 = weight assigned to the mid-term W4 = weight assigned to the final MAX: 75W1 + 94W2 + 85W3 + 92W4 Subject to: W1 + W2 + W3 + W4 = 1 W3 + W4 ≤ 0.70 W3 + W4 ≥ 0.50 0.05 ≤ W1 ≤ 0.25 0.05 ≤ W2 ≤ 0.25 0.10 ≤ W3 ≤ 0.40 0.10 ≤ W4 ≤ 0.40 Exhibit 4.2 The following questions correspond to the problem below and associated Analytic Solver Platform sensitivity report. Robert Hope received a welcome surprise in this management science class;the instructor has decided to let each person define the percentage contribution to their grade for each of the graded instruments used in the class.These instruments were: homework,an individual project,a mid-term exam,and a final exam.Robert's grades on these instruments were 75,94,85,and 92,respectively.However,the instructor complicated Robert's task somewhat by adding the following stipulations: · homework can account for up to 25% of the grade,but must be at least 5% of the grade; · the project can account for up to 25% of the grade,but must be at least 5% of the grade; · the mid-term and final must each account for between 10% and 40% of the grade but cannot account for more than 70% of the grade when the percentages are combined;and · the project and final exam grades may not collectively constitute more than 50% of the grade.The following LP model allows Robert to maximize his numerical grade. Let <sup>W</sup><sub>1 </sub><sup>= weight assigned to homework </sup>W<sub>2 </sub>= weight assigned to the project W<sub>3 </sub>= weight assigned to the mid-term W<sub>4 </sub>= weight assigned to the final MAX: <sup>75W</sup><sub>1 </sub><sup>+ 94W</sup><sub>2 </sub><sup>+ 85W</sup><sub>3 </sub><sup>+ 92W</sup><sub>4</sub> Subject to: <sup>W</sup><sub>1 </sub><sup>+ W</sup><sub>2 </sub><sup>+ W</sup><sub>3 </sub><sup>+ W</sup><sub>4 </sub><sup>= 1</sup> W<sub>3 </sub>+ W<sub>4 </sub>≤ 0.70 W<sub>3 </sub>+ W<sub>4 </sub>≥ 0.50 0.05 ≤ W<sub>1 </sub>≤ 0.25 0.05 ≤ W<sub>2 </sub>≤ 0.25 0.10 ≤ W<sub>3 </sub>≤ 0.40 0.10 ≤ W<sub>4 </sub>≤ 0.40    -Refer to Exhibit 4.2.Constraint cell F9 corresponds to the constraint,W<sub>1 </sub>+ W<sub>2 </sub>+ W<sub>3 </sub>+ W<sub>4 </sub>= 1,and has a shadow price of 75.Armed with this information,what can Robert request of his instructor regarding this constraint? -Refer to Exhibit 4.2.Constraint cell F9 corresponds to the constraint,W1 + W2 + W3 + W4 = 1,and has a shadow price of 75.Armed with this information,what can Robert request of his instructor regarding this constraint?

(Essay)
4.8/5
(27)

Analytic Solver Platform provides sensitivity analysis information on all of the following except the

(Multiple Choice)
4.9/5
(38)

A formulation has 20 variables and 8 constraints not counting non-negativity).How many variables are nonbasic?

(Multiple Choice)
4.8/5
(35)

When the allowable increase or allowable decrease for the objective function coefficient of one or more variables is zero it indicates in the absence of degeneracy)that

(Multiple Choice)
4.9/5
(32)

Benefits of sensitivity analysis include all the following except:

(Multiple Choice)
4.9/5
(27)

What is the value of the objective function if X1 is set to 0 in the following Limits Report? Cell Target Name Value \ E\ 5 Unit profit: Total Profit: 3200 Adjustable Lower Target Upper Target Cell Name Value Limit Result Limit Result $B$4 Number to make: X1 80 0 800 79.99999999 3200 $C$4 Number to make: X2 20 0 2400 20 3200

(Multiple Choice)
4.9/5
(34)

The coefficients in an LP model cj,aij,bj)represent

(Multiple Choice)
4.7/5
(32)

Jones Furniture Company produces beds and desks for college students.The production process requires carpentry and varnishing.Each bed requires 6 hours of carpentry and 4 hour of varnishing.Each desk requires 4 hours of carpentry and 8 hours of varnishing.There are 36 hours of carpentry time and 40 hours of varnishing time available.Beds generate $30 of profit and desks generate $40 of profit.Demand for desks is limited so at most 8 will be produced. How much can the price of Desks drop before it is no longer profitable to produce them? Base your response on the following Analytic Solver Platform sensitivity output. Let X1 = Number of Beds to produce X2 = Number of Desks to produce The LP model for the problem is MAX: 30 X1 + 40 X2 Subject to: 6 X1 + 4 X2 ? 36 carpentry) 4 X1 + 8 X2 ? 40 varnishing)X2 ? 8 demand for X2) X1,X2 ? 0  Changing Calls \text { Changing Calls } Cell Name Final Value Reduced Cost Objective Coefficient Allowable Increase Allowable Decrease \ B\ 4 Number to make: Beds 4 0 30 30 10 \ C\ 4 Number to make: Desks 3 0 40 20 20  Coustraints \text { Coustraints } Cell Name Final Value Shadow Price Constraint R.H. Side Allowable Increase Allowable Decrease \ \ 8 Carpentry Used 36 2.5 36 24 16 \ \ 9 Varnishing Used 40 3.75 40 26.67 16 \ \ 10 Desk demand Used 3 0 8 1+30 5

(Essay)
4.8/5
(35)

The simplex method of linear programming LP):

(Multiple Choice)
4.7/5
(29)

Jones Furniture Company produces beds and desks for college students.The production process requires carpentry and varnishing.Each bed requires 6 hours of carpentry and 4 hour of varnishing.Each desk requires 4 hours of carpentry and 8 hours of varnishing.There are 36 hours of carpentry time and 40 hours of varnishing time available.Beds generate $30 of profit and desks generate $40 of profit.Demand for desks is limited so at most 8 will be produced. Suppose the company can purchase more varnishing time for $3.00,should it be purchased and how much can be bought before the value of the additional time is uncertain? Base your response on the following Analytic Solver Platform sensitivity output. Let X1 = Number of Beds to produce X2 = Number of Desks to produce The LP model for the problem is MAX: 30 X1 + 40 X2 Subject to: 6 X1 + 4 X2 ? 36 carpentry) 4 X1 + 8 X2 ? 40 varnishing)X2 ? 8 demand for X2) X1,X2 ? 0  Changing Calls \text { Changing Calls } Cell Name Final Value Reduced Cost Objective Coefficient Allowable Increase Allowable Decrease \ B\ 4 Number to make: Beds 4 0 30 30 10 \ C\ 4 Number to make: Desks 3 0 40 20 20  Coustraints \text { Coustraints } Cell Name Final Value Shadow Price Constraint R.H. Side Allowable Increase Allowable Decrease \ \ 8 Carpentry Used 36 2.5 36 24 16 \ \ 9 Varnishing Used 40 3.75 40 26.67 16 \ \ 10 Desk demand Used 3 0 8 1+30 5

(Essay)
4.8/5
(47)

A change in the right hand side of a constraint changes

(Multiple Choice)
4.8/5
(43)

Analytic Solver Platform provides all of the following reports except

(Multiple Choice)
4.9/5
(28)

What is the value of the slack variable in the following constraint when X1 and X2 are nonbasic and only non- negativity is used as simple bounds? X1 + X2 + S1 = 100

(Multiple Choice)
4.8/5
(32)

The allowable decrease for a changing cell decision variable)is

(Multiple Choice)
4.8/5
(36)

What needs to be done to the two constraints in order to convert the problem to a standard form? MAX: 8 X1 + 4 X2 Subject to: 5 X1 + 5 X2 ≤ 20 6 X1 + 2 X2 ≤ 18 X1,X2 ≥ 0

(Multiple Choice)
4.7/5
(39)

Solve this problem graphically.What is the optimal solution and what constraints are binding at the optimal solution? MAX: 8 X1 + 4 X2 Subject to: 5 X1 + 5 X2 ≤ 20 6 X1 + 2 X2 ≤ 18 X1,X2 ≥ 0

(Essay)
4.9/5
(34)
Showing 21 - 40 of 77
close modal

Filters

  • Essay(0)
  • Multiple Choice(0)
  • Short Answer(0)
  • True False(0)
  • Matching(0)