A company chooses production quantities to make its total manufacturing cost as small as possible while meeting demand and capacity restrictions. Which expression represents the objective of the model?
5 Optimization and Decision Models Online Quiz Questions
Use this free practice quiz with 20 questions to review 5 Optimization and Decision Models, test your knowledge, and prepare for your next test or exam.
True or false: For a differentiable function on a closed interval, checking only interior points where the derivative is zero is sufficient to find the absolute maximum and minimum.
- A
True
- B
False
Three sides of a rectangular garden are fenced with 100 metres of fencing, while the fourth side borders a wall. If x is the width perpendicular to the wall, the area is A(x)=100x−2x2 for 0≤x≤50. What is the maximum area, in square metres? Enter the exact numerical value.
Complete the statements about an optimization model. A quantity under the decision maker’s control is a . An equation or inequality that restricts allowable choices is a .
A decision model has objective function P(x)=40x−x2, the constraint x≥0, and no requirement that x be an integer. How should this model be classified based on the form of its functions?
- A
A linear program
- B
An integer program
- C
A nonlinear program
- D
A binary model
True or false: For an equality-constrained optimization problem, the Lagrange multiplier condition states that the gradients of the objective and constraint are parallel at a candidate optimum.
- A
True
- B
False
What is the term for a constraint that holds with equality at an optimal solution?
Complete the Lagrange multiplier system for optimizing f(x,y) subject to g(x,y)=c. The system includes together with .
For f(x,y)=x+y on the region x≥0, y≥0, and x+y≤10, which statement is correct?
- A
The minimum is 10 at every point on x+y=10
- B
The maximum is 0 at (0,0)
- C
The maximum is 10 at every feasible point on x+y=10
- D
There is no maximum because the region has a boundary
Formulate an optimization model for a manufacturer that chooses quantities x and y of two products. Profit is $40 per unit of the first product and $30 per unit of the second, while machine time is limited by 2x+y≤100. State the variables, objective, constraints, and any appropriate variable-domain restriction. Briefly explain what must be done after formulation to identify and interpret the optimum.
A transportation model decides how many buses to use. A continuous relaxation produces x=3.6. What is the appropriate modeling response?
- A
Rounding is always valid because the objective is unchanged
- B
The variable should be declared integer from the beginning
- C
Integer restrictions matter only after the model has been solved
- D
A fractional number of buses is feasible if the fraction is small
A manufacturer chooses quantities x and y of two products. Profit is P(x,y)=40x+30y, subject to 2x+y≤100 and nonnegativity restrictions. Which part of the model is the objective function?
- A
2x+y≤100
- B
P(x,y)=40x+30y
- C
x≥0 and y≥0
- D
The set of all feasible pairs (x,y)
For a differentiable function optimized on a closed interval [a,b], which candidates must be evaluated to find an absolute maximum or minimum?
- A
Only points where f′(x)=0
- B
Only the two endpoints
- C
Interior critical numbers and both endpoints
- D
Only points where f′(x) does not exist
A transit model uses x to represent the number of buses purchased. Which modeling change is necessary before solving the optimization problem?
- A
Allow any real value of x and round only the objective value
- B
Remove the capacity constraints before solving
- C
Allow negative values so the model has more choices
- D
Require x to be an integer in the model
At a critical point of a twice-differentiable function of two variables, suppose D=fxxfyy−(fxy)2>0 and fxx>0. What does the second-derivative test conclude?
- A
A local minimum
- B
A local maximum
- C
A saddle point
- D
An inconclusive result
True or false: Checking only interior critical points is sufficient to find the absolute maximum and minimum of an objective on a closed, bounded feasible region.
- A
True
- B
False
A rectangular garden has three fenced sides and a wall as the fourth side. With 100 metres of fencing, the area is A(x)=100x−2x2 for 0≤x≤50, where x is the width perpendicular to the wall. What width x, in metres, gives the maximum area?
What term names the set of all choices that satisfy every constraint in an optimization model?
An optimization model recommends a decision using a particular objective, set of constraints, data values, and assumptions. Select all conclusions that are justified by the model's result.
- A
The recommendation is optimal only under the stated objective, data, constraints, and assumptions.
- B
Any change in an input will leave the recommendation optimal.
- C
Practical checks involving uncertainty, safety, fairness, capacity, or implementation cost may still be necessary.
- D
The recommendation is guaranteed to be best under all future conditions.
- E
Changing the objective or an important input may require the model to be reevaluated.
An optimization procedure identifies an interior point as a local maximum of an objective function. Select all statements that are logically justified by this information alone.
- A
The objective value is at least as large as nearby feasible objective values.
- B
The point is automatically the global maximum over every feasible point.
- C
Other feasible candidates may need to be examined before claiming a global maximum.
- D
The local result alone does not establish that no better feasible point exists elsewhere.
- E
A local maximum can never also be a global maximum.