SOLUTION: a predator requires 21 units of food A 12 units of food B, and 21 units of food C as its average daily consumption. these requirements are satisfied by feeling on two prey species.

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Question 1171791: a predator requires 21 units of food A 12 units of food B, and 21 units of food C as its average daily consumption. these requirements are satisfied by feeling on two prey species. one prey of species A, provides 6,2 and 3 units of food of A,B, and C, respectively. to capture and digest a prey of species B provides 3,3 and 5 units of A, B and C, respectively. to capture and digest a prey of species A requires 7 units of energy, on the average. the corresponding energy. How many preys of each should the predator capture to meet its food requirement with minimum expenditure? find the objective function, constraints and max/min value.
Found 2 solutions by CPhill, ikleyn:
Answer by CPhill(1959) About Me  (Show Source):
You can put this solution on YOUR website!
Let's break down this problem step-by-step to formulate it as a linear programming problem and find the solution.
**1. Define Variables**
* Let `x` be the number of prey of species A captured.
* Let `y` be the number of prey of species B captured.
**2. Formulate the Objective Function**
* The objective is to minimize the energy expenditure.
* Energy cost for species A: 7 units per prey
* Energy cost for species B: 5 units per prey
* Objective function (minimize energy): `Z = 7x + 5y`
**3. Formulate the Constraints**
* **Food A:** 6x + 3y ≥ 21
* **Food B:** 2x + 3y ≥ 12
* **Food C:** 3x + 5y ≥ 21
* **Non-negativity:** x ≥ 0, y ≥ 0 (You can't have negative prey)
**4. Solve the Linear Programming Problem**
We'll use a graphical method to find the feasible region and the optimal solution.
* **Graph the Constraints:**
* 6x + 3y = 21 (or 2x + y = 7)
* 2x + 3y = 12
* 3x + 5y = 21
* **Find the Intersection Points:**
* Intersection of 2x + y = 7 and 2x + 3y = 12:
* Subtract the first equation from the second: 2y = 5, y = 2.5
* Substitute y = 2.5 into 2x + y = 7: 2x + 2.5 = 7, 2x = 4.5, x = 2.25
* (2.25, 2.5)
* Intersection of 2x + y = 7 and 3x + 5y = 21
* multiply 2x+y=7 by 5. 10x+5y=35
* subtract 3x+5y=21. 7x = 14 x=2
* 2(2)+y=7. y=3
* (2,3)
* Intersection of 2x + 3y = 12 and 3x + 5y = 21
* multiply 2x+3y=12 by 3. 6x+9y=36
* multiply 3x+5y=21 by 2. 6x+10y=42
* subtract 6x+9y=36 from 6x+10y=42. y=6
* 2x+3(6)=12 2x=-6 x=-3. This is not in the feasible region.
* **Find the Corner Points of the Feasible Region:**
* (0, 7) (from 2x+y=7)
* (6,0) (from 2x+3y=12)
* (7,0) (from 3x+5y=21)
* (0,4) (from 2x+3y=12)
* (0,4.2) (from 3x+5y=21)
* (2.25,2.5)
* (2,3)
* **Evaluate the Objective Function at Each Corner Point:**
* Z(0, 7) = 7(0) + 5(7) = 35
* Z(6, 0) = 7(6) + 5(0) = 42
* Z(7, 0) = 7(7) + 5(0) = 49
* Z(0, 4.2) = 7(0) + 5(4.2) = 21
* Z(2.25, 2.5) = 7(2.25) + 5(2.5) = 15.75 + 12.5 = 28.25
* Z(2, 3) = 7(2) + 5(3) = 14 + 15 = 29
* **Determine the Minimum Value:**
* The minimum value of Z is 28.25 at (2.25, 2.5). However, since we can't have fractional prey, we need to examine the integer points surrounding (2.25,2.5). Those points are (2,3) and (3,2).
* Z(2,3) = 29
* Z(3,2) = 7(3)+5(2) = 21+10=31
* The minimum integer value is 29 at (2,3).
**Results**
* **Objective Function:** Z = 7x + 5y (minimize energy)
* **Constraints:**
* 6x + 3y ≥ 21
* 2x + 3y ≥ 12
* 3x + 5y ≥ 21
* x ≥ 0, y ≥ 0
* **Minimum Value:** 29
* **Solution:** The predator should capture 2 prey of species A and 3 prey of species B.

Answer by ikleyn(52749) About Me  (Show Source):
You can put this solution on YOUR website!
.
a predator requires 21 units of food A 12 units of food B, and 21 units of food C as its average daily consumption.
these requirements are satisfied by feeling on two prey species.
one prey of species A, provides 6,2 and 3 units of food of A,B, and C, respectively.
to capture and digest a prey of species B provides 3,3 and 5 units of A, B and C, respectively.
to capture and digest a prey of species A requires 7 units of energy, on the average.
the corresponding energy.
How many preys of each should the predator capture to meet its food requirement with minimum expenditure?
find the objective function, constraints and max/min value.
~~~~~~~~~~~~~~~~~~~~~~~~~


            Regarding this "problem" in the post, I have several notices.


(1)  The meaning of the post is unclear. The species are mixed with food (go under the same names).

     It turns the problem into the soup of words.

     Undoubtedly, it is IMPOSSIBLE to consider such a text as a Math problem.


(2)  How @CPhill interprets it - - - it does not matter.

     If the problem's meaning is unclear from its text, interpretations will not help.


(3)  In his post, @CPhill writes for the energy function to minimize

        Z = 7x + 5y.

     In the text, NOTHING does point to this formula. 
     So, it makes the solution by @CPhill  IRRELEVANT.



(4)  In the solution, @CPhill proposes to make a lot of unnecessary job  calculating the objective
     function in corner points that do not belong to the feasibility domain.


                                    The CONCLUSIONS:


The text in the post CAN NOT be interpreted as a Math problem.
This "problem's" right place is in the garbage bin.

Interpretation by @CPhill is not adequate and is not relevant to the problem.

The solution in the post by @CPhill is WRONG WAY TEACHING.

For the safety of you mind, simply ignore the problem and the post by @CPhill.


   * * * * DO  NOT  CONSIDER  THIS  GIBBERISH  seriously. * * * *



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                Regarding the post by @CPhill . . .


Keep in mind that @CPhill is a pseudonym for the Google artificial intelligence.

The artificial intelligence is like a baby now. It is in the experimental stage
of development and can make mistakes and produce nonsense without any embarrassment.


                It has no feeling of shame - it is shameless.


This time, again,  it made an error.


Although the @CPhill' solution are copy-paste  Google  AI solutions,  there is one essential difference.

Every time,  Google  AI  makes a note at the end of its solutions that  Google  AI  is experimental
and can make errors/mistakes.

All @CPhill' solutions are copy-paste of  Google  AI  solutions, with one difference:
@PChill never makes this notice and never says that his solutions are copy-past that of Google.
So, he NEVER SAYS TRUTH.

Every time,  @CPhill embarrassed to tell the truth.
But I am not embarrassing to tell the truth,  as it is my duty at this forum.


And the last my comment.

When you obtain such posts from @CPhill,  remember,  that  NOBODY  is responsible for their correctness,
until the specialists and experts will check and confirm their correctness.

Without it,  their reliability is  ZERO and their creadability is  ZERO,  too.


Plus one comment specially for the developers of this AI.

The most weak feature of your current development is that this current AI
is unable to recognize idiotic "problems" and to distinct them from regular Math problems.