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Savannah is making pots and plates to sell at a local art fair. Each pot weighs 2 pounds and each plate weighs 1 pound. Savannah cannot carry more than 50 pounds to the fair . She only has enough clay to make 40 plates. In addition, she only has enough clay to make 24 pots. She will make $12 profit on every plate and $25 for every pot that she sells. How many pots and how many plates should Savannah make to maximize her profit?

Define the variable
Write the constraints
What is the Objective Equation

User Jasaarim
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2 Answers

6 votes

Answer:

Variables
X = number of pots made and Y = number of plates made

Constraints
2X + 1Y ≤ 50
X ≤ 24
Y ≤ 40
X ≥ 0, Y ≥ 0

Objective Equation
P = 25X + 12Y
where P is profit in $

Solution:

24 pots and 2 plates for a total profit of $624

Explanation:

This is an example of a Linear Programming( LP) problem where the objective is to maximize or minimize a function subject to constraints (inequalities) which are linear in nature

To proceed, first define variables to represent the number of pots and pans Savannah has to make

Let X represent the number of pots and Y the number of plates that Savannah finally makes at maximum profit

Constraint 1: Weight constraint
Since each pot weighs 2 pounds, X pots will weigh 2X pounds
Each plate weighs 1 pound so Y plates will weigh 1Y pounds

The sum of these weights cannot exceed 50 pounds i.e ≤ 50 pounds
So first constraint is
2X + 1Y ≤ 50

Constraint 2: Clay resource constraint

Savannah has only enough clay to make 40 plates . So the number of plates she can make is subject to the constraint
Y ≤ 40

Similarly with only enough clay to make 24 pots, the next resource constraint would be
X ≤ 24

(Remember X = number of pots and Y = number of plates - they are trying to trick you by interchanging pots and pans in the statements)

Each pot gets her a profit of $25 and each plate gives her a profit of $12

So the profit P she can expect to get by selling X pots and Y plates is given by the equation
P = 25X + 12Y


This is the objective function or objective equation

So here are the answers

Variables: X = number of pots made and Y = number of plates made

Constraints
2X + 1Y ≤ 50 (Weight Constraint)
X ≤ 24 (Clay constraint for pots)
Y ≤ 40 ((Clay constraint for pots)
X ≥ 0, Y ≥ 0 ( we add these to make sure X, Y cannot be negative)

Objective Equation : P = 25X + 12Y

Objective is to maximize 25X + 12Y

The entire LP problem is stated as below

Max 25X + 12Y

subject to:
2X + 1Y ≤ 50 (Weight Constraint)
X ≤ 24 (Clay constraint for pots)
Y ≤ 40 ((Clay constraint for pots)
X ≥ 0, Y ≥ 0

To solve:
Best solved using an LP calculator but I will provide the graphical solution method


If we graph all these inequalities we get a "feasible" region which is the region falling within all inequalities. We select the corner points of this region and plug in these X and Y values inside the objective equation and see which (X,Y) maximizes

Look at the attached graph:
The feasible region is the figure ABCD with corner points
A(0,0), B(0, 40), C(5,40), D(24, 2) and E (24,2)

The maximum will correspond to one of these corner points

We can easily see that C(5,40) is superior to B(0,40) so discard B as a possible solution point

Similarly we can see that D(24,2) is superior to D(24,0) so discard point E

We have two choices corresponding to points C and D. Plugging in the

X, Y values of these two points in the objective equation will give us the value of profit at each of those points

Choose the X, Y values which have a higher P value
At C(5, 40) we get P = 25 x 5 + 12 x 40 = $605

At D(24, 2) we get P = 25 x 24 + 2 x 12 = $624

Therefore Savannah should make 24 pots and 2 plates for a total profit of $624


Savannah is making pots and plates to sell at a local art fair. Each pot weighs 2 pounds-example-1
User Garik
by
4.1k points
4 votes

Answer:

90

Explanation:

User Ravena
by
4.2k points