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
111 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 formula for finding the measure of an angle in a triangle given the lengths of two sides?
+
Math question: Find the limit of (3x^2 + 5x - 1)/(2x - 3) as x approaches 2.
+
Math question: What is the value of f(x) = 2x + 5 when x = 3? (
+
New questions in Mathematics
2(2+2x)=12
The random variable Y is defined as the sum between two different integers selected at random between -4 and 2 (both included). What are the possible values of the random variable Y? What is the value of P(Y=-3)? And whether it is less than or equal to -5?
*Question!!* *Victory saved 3,000 in first bank and 2,000 Naira in union bank PSC with interest rate of X% and Y% per annual respectively his total interest in one year is #640. If she has saved 2,000 naira with first bank and 3,000 naira in union bank for same period she would have made extra 20# as additional interest, then find the value of X and Y
Moaz wanted to test whether the level of headache pain (on a scale of 1 – 10) changes after taking Advil. He collected data from 9 participants and calculated the difference in headache pain before and after taking Advil (summarized in the table below). Determine W observed for this test. Difference Scores -2 -4 0 +1 +3 -2 0 -3 -5 Also, What is the degrees of freedom for this test?
Director of reservations believes that 9% of the ticketed passengers are no-shows. If the directors right what is the probability that the proportion of no-shows in a sample of 789 ticketed passengers with differ from the population proportion buy more than 3% round your answer to four decimal places.
4. Show that if n is any integer, then n^2 3n 5 is an odd integer
Mrs. Emily saved RM10000 in a bank. At the end of the eighth year, the amount of money accumulated amounted to RM19992.71. If the bank pays an annual interest of x% for a year compounded every 6 months. Calculate the value of x.
The Humane Society has asked for our help again this week. Currently they are charging $50 for an adoption fee. Unfortunately they just pulled this number out of the air and do not know why they are charging this amount. They would like to charge an amount that covers all the adoption costs – both the variable costs for adoptions as well as the fixed cost for the kennel portion of the Humane Shelter operations. We can help them by doing a breakeven analysis. During a client meeting we gathered these facts. There are 2 part-time employees that each earn $1000 per month. The utilities for the kennel area (water, electricity) are $200 per month. The average food cost for animals in the kennel is $800 per month. In addition, each animal that is adopted receives a rabies vaccination that costs $4 and is micro-chipped that costs $6. At the current cost of $50, how many animals must be adopted to break-even? What would break-even be at a $60 adoption fee? What would break-even be if the fee were lowered to $40? The newspaper has suggested that the Humane Society advertise to increase pet adoptions. The package that they have recommended costs $1000 for a very small ad run every day for a month. If the Humane Society does this extra advertising, how will it affect breakeven? Based on what you have learned about elasticity, what price do you recommend for the adoption fee?
Your boss asks you to plan the sample size for a randomized, double-blind, controlled trial in the clinical development of a cure for irritable bowl disease. Current standard treatment shall be compared with a new treatment in this trial. The S3-guideline of AWM demonstrated a mean change of the summary score of the validated health related quality of life questionnaire at 8 weeks of 16 with standard deviation 23 under standard treatment. You quote the drop-out rate of 11% from literature (previous phase of clinical development). Your research yielded a clinically important effect of 4 that has been found to be the Minimal Clinically Important Difference (MCID). In order to demonstrate superiority of the new treatment over standard of care, you assume that the change in of the summary score of the validated health related quality of life questionnaire follows a normal distribution, and that the standard deviation is the same for both treatments. How many patientes would one need to recruit for the trial to demonstrate the clinically interesting difference between treatments at significance level 5% with 95% power?
A company receives sales in $20 per book and $18 per calculator. The per unit cost to manufacture each book and calculator are $5 and 4$ respectively. The monthly (30 day) cost must not exceed $27000 per month. If the manufacturing equipment used by the company takes five minutes to produce a book and 15 minutes to produce a calculator, how many books and calculators should the company produce to maximise profit? Please solve graphically and
A machine produces 255 bolts in 24 minutes. At the same rate, how many bolts would be produced in 40 minutes?
A bag has 4 green lollipops, 3 white lollipops, and 1 black lollipop. What is the probability of drawing a white lollipop?
Take the limit of (sin(x-4))/(tan(x^2 - 16) as x approaches 4.
The business college computing center wants to determine the proportion of business students who have personal computers (PC's) at home. If the proportion is greater than 35%, then the lab will modify a proposed enlargement of its facilities. Suppose a hypothesis test is conducted and the test statistic is z= 2.6. Find the P-value for this test.
a survey showed that 3 out of 7 voters would vote in an election. based on this survey, how many people would vote in a city with 25,000 people?
Let x be an integer. Prove that x^2 is even if and only if is divisible by 4.
Which statement best describes the key changes in perspectives on inclusion? An inclusive program must consider the unique experiences of every child and family as well as the child's strengths and needs. There is a shift in thinking about individual programs as "inclusive programs" to thinking about inclusion as something that reflects the cultural influence of the family. There is a greater emphasis on barriers to full participation and the acknowledgement that all children are unique and must be fully and meaningfully engaged in a program. In an inclusive program all participants are accepted by their peers and other members of the community.
find missing measure for triangle area = 48 m square base = 10m heaighy = ? m
1. A jeweler has two gold bars, with 80% purity and the other with 95% purity. How much of each must be melted to obtain a 5 kilo ingot with 86% purity?
A post office has three categories of letters: 60% are from businesses, 30% are individual mail, and the remaining 10% are government mail. 5% of the letters from businesses have address errors, 10% of the individual mail has address errors, while 1% of the government mail has address errors. If we receive a letter with an address error, what is the probability that it is individual mail?"