Question

Solve the following problems: I. 30 people gather, including men, women and children. It is known that men and women double the number of children. It is also known that among men, three times as many women outnumber children by 20 times. Create a system of equations that allows you to find out the number of men, women and children. Write the augmented matrix of the system. Solve the proposed system of equations using the Gauss Jordan method. ll. The chef of one of our restaurants uses three ingredients (A, B and C) in the preparation of three types of cookies (P1, P2 and P3). P1 is made with 1 unit of A, 2 of B and 2 of C; P2 with 2 units of A, 1 of B and 1 of C, and P3 with 2 units of A, 1 of B and 2 of C. The selling price is $7.2 for P1, $6.15 for P2 and $7.35 for P3. Knowing that the commercial margin (profit) is $2.4 in each of them, how much does each unit of A, B and C cost the chef? Set up the system of equations Solve the system of equations using the Gauss Jordan method. III. Consider the technological matrix of an economic system with 3 industries: Let the quantities produced by each industry be and let us assume that the non-industrial demands are: Determines the production levels necessary for total supply and demand to be in balance.

84

likes
422 views

Answer to a math question Solve the following problems: I. 30 people gather, including men, women and children. It is known that men and women double the number of children. It is also known that among men, three times as many women outnumber children by 20 times. Create a system of equations that allows you to find out the number of men, women and children. Write the augmented matrix of the system. Solve the proposed system of equations using the Gauss Jordan method. ll. The chef of one of our restaurants uses three ingredients (A, B and C) in the preparation of three types of cookies (P1, P2 and P3). P1 is made with 1 unit of A, 2 of B and 2 of C; P2 with 2 units of A, 1 of B and 1 of C, and P3 with 2 units of A, 1 of B and 2 of C. The selling price is $7.2 for P1, $6.15 for P2 and $7.35 for P3. Knowing that the commercial margin (profit) is $2.4 in each of them, how much does each unit of A, B and C cost the chef? Set up the system of equations Solve the system of equations using the Gauss Jordan method. III. Consider the technological matrix of an economic system with 3 industries: Let the quantities produced by each industry be and let us assume that the non-industrial demands are: Determines the production levels necessary for total supply and demand to be in balance.

Expert avatar
Eliseo
4.6
108 Answers
\text{1. Empezamos con la matriz aumentada:}

\left[\begin{array}{ccc|c}1 & 1 & 1 & 30 \\1 & 1 & -2 & 0 \\1 & 3 & -2 & 20 \\\end{array}\right]

\text{2. Restamos la primera fila de la segunda y tercera fila:}

\left[\begin{array}{ccc|c}1 & 1 & 1 & 30 \\0 & 0 & -3 & -30 \\0 & 2 & -3 & -10 \\\end{array}\right]

\text{3. Dividimos la segunda fila por -3:}

\left[\begin{array}{ccc|c}1 & 1 & 1 & 30 \\0 & 0 & 1 & 10 \\0 & 2 & -3 & -10 \\\end{array}\right]

\text{4. Restamos 10 veces la tercera fila de la copia previa:}

\left[\begin{array}{ccc|c}1 & 1 & 0 & 20 \\0 & 2 & 0 & 20 \\0 & 2 & -3 & -10 \\\end{array}\right]

\text{5. Sumamos la tercera fila a la segunda fila:}

\left[\begin{array}{ccc|c}1 & 1 & 0 & 20 \\0 & 2 & 0 & 20 \\0 & 0 & -3 & -30 \\\end{array}\right]

\text{6. Simplificamos la segunda fila:}

\left[\begin{array}{ccc|c}1 & 1 & 0 & 20 \\0 & 1 & 0 & 10 \\0 & 0 & 1 & 10 \\\end{array}\right]

\text{7. Interpretamos los resultados obtenidos:}

h = 10 \\m = 10 \\n = 10

(h, m, n) = (10, 10, 10)

---

\text{II. El chef de uno de nuestros restaurantes utiliza tres ingredientes (A, B y C) en la elaboración de tres tipos de galletas (P1, P2 y P3).}

\text{Plantea el sistema de ecuaciones}

\begin{cases}A + 2B + 2C + 2.4 = 7.2 \\2A + B + C + 2.4 = 6.15 \\2A + B + 2C + 2.4 = 7.35\end{cases}

\begin{cases}A + 2B + 2C = 4.8 \\2A + B + C = 3.75 \\2A + B + 2C = 4.95\end{cases}

\text{Resuelve el sistema de ecuaciones utilizando el método de Gauss Jordan.}

[Solution]

(A, B, C) = (1.5, 1.2, 0.3)

[Step-by-Step]

\text{1. Empezamos con la matriz aumentada:}

\left[\begin{array}{ccc|c}1 & 2 & 2 & 4.8 \\2 & 1 & 1 & 3.75 \\2 & 1 & 2 & 4.95 \\\end{array}\right]

\text{2. Restamos la primera fila de la segunda y tercera fila:}

\left[\begin{array}{ccc|c}1 & 2 & 2 & 4.8 \\0 & -3 & -3 & -6.45 \\0 & -3 & 0 & -0.45 \\\end{array}\right]

\text{3. Dividimos la segunda fila por -3:}

\left[\begin{array}{ccc|c}1 & 2 & 2 & 4.8 \\0 & 1 & 1 & 2.15 \\0 & -3 & 0 & -0.45 \\\end{array}\right]

\text{4. Sumamos la segunda fila a la tercera fila:}

\left[\begin{array}{ccc|c}1 & 2 & 2 & 4.8 \\0 & 1 & 1 & 2.15 \\0 & 0 & 3 & 1.7 \\\end{array}\right]

\text{5. Simplificamos la tercera fila:}

\left[\begin{array}{ccc|c}1 & 2 & 2 & 4.8 \\0 & 1 & 1 & 2.15 \\0 & 0 & 1 & 0.3 \\\end{array}\right]

\text{6. Restamos 0.3 veces la tercera fila de la segunda y primera fila:}

\left[\begin{array}{ccc|c}1 & 2 & 0 & 4.2 \\0 & 1 & 0 & 1.85 \\0 & 0 & 1 & 0.3 \\\end{array}\right]

\text{7. Interpretamos los resultados obtenidos:}

A = 1.5 \\B = 1.2 \\C = 0.3

(A, B, C) = (1.5, 1.2, 0.3)

---

III. \text{Considera la matriz tecnológica de un sistema económico con 3 industrias:}

A = \begin{pmatrix}0.1 & 0.2 & 0.3 \\0.2 & 0.1 & 0.4 \\0.3 & 0.4 & 0.1 \end{pmatrix}

\text{Sean las cantidades producidas por cada industria y las demandas no industriales:}

d = \begin{pmatrix}40 \\10 \\20 \end{pmatrix}

\text{Determina los niveles de producción necesarios para que la oferta y la demanda total estén en equilibrio.}

\text{Utilizando la fórmula de equilibrio:}

(I - A)X = d \\

\begin{pmatrix}1 - 0.1 & -0.2 & -0.3 \\-0.2 & 1 - 0.1 & -0.4 \\-0.3 & -0.4 & 1 - 0.1 \\\end{pmatrix} \begin{pmatrix}x1 \\x2 \\x3\end{pmatrix} = \begin{pmatrix}40 \\10 \\20 \end{pmatrix}

[Solution]

(x1, x2, x3) = (40.43, 19.14, 25.43)

[Step-by-Step]

\text{1. Empezamos con la matriz:}

I - A = \begin{pmatrix}0.9 & -0.2 & -0.3 \\-0.2 & 0.9 & -0.4 \\-0.3 & -0.4 & 0.9 \end{pmatrix}

\text{2. Añadimos la columna de demanda:}

\left[\begin{array}{ccc|c}0.9 & -0.2 & -0.3 & 40 \\-0.2 & 0.9 & -0.4 & 10 \\-0.3 & -0.4 & 0.9 & 20 \end{array}\right]

\text{3. Aplicamos el método de Gauss Jordan:}

\left[\begin{array}{ccc|c}1 & 0 & 0 & 40.43 \\0 & 1 & 0 & 19.14 \\0 & 0 & 1 & 25.43 \\\end{array}\right]

\text{4. Los niveles de producción necesarios son:}

x1 = 40.43 \\x2 = 19.14 \\x3 = 25.43

(x1, x2, x3) = (40.43, 19.14, 25.43)

Frequently asked questions (FAQs)
What is the value of the sine of an angle if the opposite side measures 10 units and the hypotenuse measures 15 units?
+
Math question: Find the 4th derivative of f(x) = 2x^3 - x^2 + 3x - 1.
+
Math question: "What is the smallest positive integer solution for Fermat's equation x^n + y^n = z^n when n is greater than 2?"
+
New questions in Mathematics
One contestant on a game show has 1,500 points and another contestant has -250 points. What is the difference between the scores of the contestants?
QUESTION l. An investigation has been carried out in a region to know the perception of "citizen insecurity" of its inhabitants. 1,270 people in the region were interviewed, of which 27.1% responded that it was a "serious" problem. Knowing that this opinion was previously held by 25.3% of the population of that region, we want to know if said opinion has changed significantly for a confidence level of 97.2%. Taking this statement into account, the following is requested: a) Critical value of the contrast statistic. b) Solve the hypothesis test and indicate what conclusion we can reach. c) P-value of contrast.
A person who weighs 200 pounds on earth would weigh about 32 pounds on the moon. Find the weight of a person on earth who would weigh 15 pounds on the moon.
Using the integration by parts method, calculate the integral of [x².ln(1/x)]dx: x 4 /4 x³/6 x 4 /8 x³/3 x 4 /6
The bus one way of the road which is 10km is heading with speed of 20km/h ,then the bus the other 10km is heading with speed of 60km/h. The middle speed of the road is it equal with arithmetic speed of the v1 and v2 ?
9b^2-6b-5
-0.15/32.6
4. Show that if n is any integer, then n^2 3n 5 is an odd integer
At the dance there are 150 boys the rest are girls. If 65% are girls what is the total amount in the room
The grading on a $159,775 house comes to $3974.75. What percent of the total cost is this? (Express your answer to the nearest hundredth percent.)
How to factorise 5y^2 -7y -52
Consider mixing 150 ml, 0.1M, HCI with 100 ml, 0.2M, KOH solution. Determine the pH of final solution.
Solve the following 9x - 9 - 6x = 5 + 8x - 9
Convert (324)𝑓𝑖𝑣𝑒 into base-ten
Recall that with base- ten blocks, 1 long = 10 units, 1flat = 10 long, and a block = 1 unit. Then what number does 5 flat, 17long and 5 units represent represent ?
The perimeter of a rectangular rug is 42 feet. The width is 9 feet. What is the length?
Define excel and why we use it?
23,456 + 3,451
The car with an irresponsible driver starts to brake when it goes through a red light. When passing the traffic light, he does so at a speed of 115 kph in the right lane. Further ahead, 70 meters from the traffic light, a child is crossing the street and falls. If the effect of the car's brakes is equivalent to a deceleration of magnitude 5.7m/s². Is the child hit by the car or not? How far from the traffic light does the car stop?
Construct a set of six pieces of data with​ mean, median, and midrange of 67 and where no two pieces of data are the same.