[10] In the following given system, determine a matrix A and vector b so that the system can be represented as a matrix equation in the form AX = b. In the given linear system, solve for y without solving for X, Z and w by using Cramer's rule, x + y + 2 + 2w = 3. -7x – 3y + 5z - 8w = -3 4x + y + z + w = 6 3x + 7y - Z + w = 1

Answers

Answer 1

Answer:

[tex]y=-\frac{158}{579}[/tex]

Step-by-step explanation:

To find the matrix A, took all the numeric coefficient of the variables, the first column is for x, the second column for y, the third column for z and the last column for w:

[tex]A=\left[\begin{array}{cccc}1&1&2&2\\-7&-3&5&-8\\4&1&1&1\\3&7&-1&1\end{array}\right][/tex]

And the vector B is formed with the solution of each equation of the system:[tex]b=\left[\begin{array}{c}3\\-3\\6\\1\end{array}\right][/tex]

To apply the Cramer's rule, take the matrix A and replace the column assigned to the variable that you need to solve with the vector b, in this case, that would be the second column. This new matrix is going to be called [tex]A_{2}[/tex].

[tex]A_{2}=\left[\begin{array}{cccc}1&3&2&2\\-7&-3&5&-8\\4&6&1&1\\3&1&-1&1\end{array}\right][/tex]

The value of y using Cramer's rule is:

[tex]y=\frac{det(A_{2}) }{det(A)}[/tex]

Find the value of the determinant of each matrix, and divide:

[tex]y==\frac{\left|\begin{array}{cccc}1&3&2&2\\-7&-3&5&-8\\4&6&1&1\\3&1&-1&1\end{array}\right|}{\left|\begin{array}{cccc}1&1&2&2\\-7&-3&5&-8\\4&1&1&1\\3&7&-1&1\end{array}\right|} =\frac{158}{-579}[/tex]

[tex]y=-\frac{158}{579}[/tex]


Related Questions

The three sides of a triangle measure 9, 20, and n. What is the range of possible lengths of n?
9 < n < 20
6 < n < 29
11 < n < 29
11 < n < 20

Answers

Answer:

11 < n < 29

Step-by-step explanation:

The  smallest the third side can be is just bigger than the difference of the other two sides

20-9 < n

11<n

The largest the third side can be is just smaller than the sum of the other two sides

20+9 > n

29 >n

Putting this together

11<n<29

You manage an ice cream factory that makes two flavors: Creamy Vanilla and Continental Mocha. Into each quart of Creamy Vanilla go 2 eggs and 3 cups of cream. Into each quart of Continental Mocha go 1 egg and 3 cups of cream. You have in stock 700 eggs and 1500 cups of cream. How many quarts of each flavor should you make in order to use up all the eggs and cream? HINT [See Example 5.]

Answers

Answer:

200 Creamy Vanilla

300 Continental Mocha

Step-by-step explanation:

3 cups cream for each:

500 Quarts total

Creamy Vanilla requires 400 eggs

Continental Mocha requres 300 eggs for a total of 700 eggs

The answer is:

[tex]\[ \boxed{V = 200, M = 300} \][/tex]

To solve this problem, we need to set up a system of equations based on the given information and then solve for the number of quarts of each flavour of ice cream that should be made.

Let [tex]\( V \)[/tex] represent the number of quarts of Creamy Vanilla ice cream and [tex]\( M \)[/tex] represent the number of quarts of Continental Mocha ice cream.

From the information given, we can derive the following equations:

For the eggs:

Each quart of Creamy Vanilla requires 2 eggs, so [tex]\( 2V \)[/tex] eggs are used for Creamy Vanilla.

Each quart of Continental Mocha requires 1 egg, so [tex]\( M \)[/tex] eggs are used for Continental Mocha.

Since there are 700 eggs in total, we have the equation:

[tex]\[ 2V + M = 700 \][/tex]

For the cream:

Each quart of Creamy Vanilla requires 3 cups of cream, so [tex]\( 3V \)[/tex] cups of cream are used for Creamy Vanilla.

Each quart of Continental Mocha also requires 3 cups of cream, so [tex]\( 3M \)[/tex] cups of cream are used for Continental Mocha.

Since there are 1500 cups of cream in total, we have the equation:

[tex]\[ 3V + 3M = 1500 \][/tex]

Now we have a system of two equations with two variables:

[tex]\[ \begin{cases} 2V + M = 700 \\ 3V + 3M = 1500 \end{cases} \][/tex]

To solve this system, we can simplify the second equation by dividing every term by 3:

[tex]\[ V + M = 500 \][/tex]

Now we have a simpler system:

[tex]\[ \begin{cases} 2V + M = 700 \\ V + M = 500 \end{cases} \][/tex]

We can subtract the second equation from the first to eliminate [tex]\( M \)[/tex] and solve for [tex]\( V \)[/tex] :

[tex]\[ (2V + M) - (V + M) = 700 - 500 \][/tex]

[tex]\[ V = 200 \][/tex]

Now that we have the value of [tex]\( V \)[/tex], we can substitute it back into the simplified second equation to find [tex]\( M \)[/tex]:

[tex]\[ 200 + M = 500 \][/tex]

[tex]\[ M = 500 - 200 \][/tex]

[tex]\[ M = 300 \][/tex]

Therefore, the factory should make 200 quarts of Creamy Vanilla and 300 quarts of Continental Mocha to use up all the eggs and cream.

The final answer is:

[tex]\[ \boxed{V = 200, M = 300} \][/tex]

You deposit $100 in an account earning 4% interest compounded annually. How much will you have in the account in 10 years? Round your answer to the nearest penny

Answers

Answer:

$148.02

Step-by-step explanation:

In the question

Principal = $100, rate(R) = 4% compounded annually, time(T)= 10 years

we know that the formula for compound interest

A=[tex]P\times_(1+\frac{R}{100} )^{T}[/tex]   where A is amount

now putting values in the above formula we get

A=[tex]100\times_(1+\frac{4}{100} )^{10}[/tex]

therefore A= $148.024428

rounding off to the nearest penny we get amount as $148.02 and compound interest will be $48.02

Use the method of cylindrical shells to find the volume V generated by rotating the region bounded by the given curves about the specified axis. y = x3, y = 8, x = 0; about x = 9

Answers

Answer:

200π cubic units.

Step-by-step explanation:

Use the general method of integrating the area of the surface  generated by an arbitrary cross section of the region  taken parallel to the axis of revolution.

Here the axis  x = 9 is parallel to the y-axis.

The height of  one cylindrical shell = 8 - x^3.

The radius = 9 - x.

                                               2

The volume generated =  2π∫   (8 - x^3) (9 - x) dx

                                               0

= 2π ∫ ( 72 - 8x - 9x^3 + x^4) dx

             2

=      2 π [    72x - 4x^2 - 9x^4/4 + x^5 / 4  ]

            0

= 2 π  ( 144 - 16  - 144/4 + 32/4)

= 2 π * 100

= 200π.

The range of for y = 4/5 sin x for pi [tex]\leq[/tex] x [tex]\leq[/tex] 3pi/2 is

Choices:
4/5 [tex]\leq[/tex] y [tex]\leq[/tex] 1
-1 [tex]\leq[/tex] y[tex]\leq[/tex] 4/5
-4/5[tex]\leq[/tex] y [tex]\leq[/tex] 0
-4/5 [tex]\leq[/tex] y[tex]\leq[/tex] 4/5

Answers

Answer:

see attachment

Step-by-step explanation:

The range of [tex]\(y = \frac{4}{5}\sin x\)[/tex] for [tex]\(\pi \leq x \leq \frac{3\pi}{2}\)[/tex] is [tex]\(-\frac{4}{5} \leq y \leq 0\)[/tex] ( Option C).

To find the range of [tex]\(y = \frac{4}{5}\sin x\)[/tex] for [tex]\(\pi \leq x \leq \frac{3\pi}{2}\)[/tex], we need to determine the minimum and maximum values of sin x in the given interval and then scale them using [tex]\(\frac{4}{5}\)[/tex].

In the interval [tex]\(\pi \leq x \leq \frac{3\pi}{2}\)[/tex], the sine function is negative since it corresponds to the third and fourth quadrants on the unit circle. The minimum value of sin x in this interval is -1, and the maximum value is 0.

Now, scale these values using [tex]\(\frac{4}{5}\)[/tex]:

[tex]\(-1 \times \frac{4}{5} = -\frac{4}{5}\) (minimum)\\\\\(0 \times \frac{4}{5} = 0\) (maximum)[/tex]

Therefore, the range of [tex]\(y = \frac{4}{5}\sin x\) for \(\pi \leq x \leq \frac{3\pi}{2}\)[/tex] is [tex]\(-\frac{4}{5} \leq y \leq 0\)[/tex]. The correct choice is:

-4/5 <= y <= 0

To know more about range, refer here:

https://brainly.com/question/17440903

#SPJ2

A father wishes to give his son P200, 000 ten years from now. What amount should he invest if it will earn interest at 10% compounded quarterly during the first five years and 12% compounded annually during the next five years? A. P68,757.82 B. P62,852.23 C. P69,256.82 D. P67,238.54

Answers

Answer:

C. P69,256.82

Step-by-step explanation:

We know that,

The amount formula in compound interest is,

[tex]A=P(1+\frac{r_1}{n_1})^{n_1t_1} (1+\frac{r_2}{n_2})^{n_2t_2}.......[/tex]

Where, P is the principal amount,

[tex]r_1, r_2....[/tex] are the annual rate for the different periods,

[tex]t_1, t_2,.....[/tex] are the number of year for different periods,

[tex]n_1, n_2, n_3...[/tex] are the number of periods,

Given,

A = P 200,000,

[tex]r_1=10%=0.1[/tex], [tex]n_1=4[/tex], [tex]t_1=5[/tex],[tex]r_2=12%=0.12[/tex], [tex]n_2=1[/tex], [tex]t_2=5[/tex]

Thus, by the above formula the final amount would be,

[tex]200000=P(1+\frac{0.1}{4})^{4\times 5}(1+\frac{0.12}{1})^{1\times 5}[/tex]

[tex]200000=P(1+0.025)^{20}(1+0.12)^5[/tex]

[tex]200000=P(1.025)^{20}(1.12)^5[/tex]

[tex]\implies P=69,256.824\approx 69,256.82[/tex]

Option C is correct.

The correct option is C. P69,256.82. The father should invest approximately P69,256.82 today to ensure his son receives P200,000 in ten years.

To determine the amount the father needs to invest today to give his son P200,000 ten years from now, we will break the problem into two phases due to different interest rates and compounding periods.

Phase 1: First Five Years (10% compounded quarterly)

→ Future Value (FV) needed after 10 years: P200,000

→ Future Value (FV) after first five years at 12% annual interest for the next five years:

Let's use the formula for compound interest to calculate amount required after the first five years.

Here,

→ n is the number of times the interest is compounded per year

→ t is time in years.

→ [tex]FV = PV*(1 + r/n)^{(nt)[/tex]

After the first five years, the amount needs to grow at 12% compounded annually for 5 years to reach P200,000.

We can calculate the present value (PV) at the end of the first five years needed to achieve P200,000 after next 5 years.

→ P200,000 = [tex]PV * (1 + 0.12/1)^{(1*5)[/tex]

→ P200,000 = [tex]PV * (1.12)^5[/tex]

Calculating PV:

→ PV = P200,000 / (1.7623)

        ≈ P113,477.57

Phase 2: First Five Years Investment Calculation

Now, we need to find out the amount the father should invest today to reach P113,477.57 after five years with 10% interest compounded quarterly.

Here,

→ r is the quarterly rate,

→ nt is the total number of quarters.

We use the same compound interest formula:

→ [tex]FV = PV * (1 + r/n)^{(nt)[/tex]

→ P113,477.57 = [tex]PV * (1 + 0.10/4)^{(4*5)[/tex]

→ P113,477.57 = [tex]PV * (1.025)^{20[/tex]

→ [tex](1.025)^{20} \approx 1.6386[/tex]

Calculating PV:

→ PV = P113,477.57 / 1.6386

        ≈ P69,256.82

So, the father needs to invest approximately P69,256.82 today.

Kristie has taken five tests in science class. The average of all five of Kristie's test scores is 94. The average of her last three test scores is 92. What is the average of her first two test scores?

Answers

Answer:  The average of the first two test scores is 97.

Step-by-step explanation:  Given that Kristie has taken five tests in science class. The average of all five of Kristie's test scores is 94 and the average of her last three test scores is 92.

We are to find the average score of her first two tests.

Let a1, a2, a3, a4 and a5 be teh scores of Kristle in first , second, third, fourth and fifth tests respectively.

Then, according to the given information, we have

[tex]\dfrac{a1+a2+a3+a4+a5}{5}=94\\\\\Rightarrow a1+a2+a3+a4+a5=94\times5\\\\\Rightarrow a1+a2+a3+a4+a5=470~~~~~~~~~~~~~~~~~~~~~~~~~~~(i)[/tex]

and

[tex]\dfrac{a3+a4+a5}{3}=92\\\\\Rightarrow a3+a4+a5=92\times3\\\\\Rightarrow a3+a4+a5=276~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~(ii)[/tex]

Subtracting equation (ii) from equation (i), we get

[tex](a1+a2+a3+a4+a5)-(a3+a4+a5)=470-276\\\\\Rightarrow a1+a2=194\\\\\Rightarrow \dfrac{a1+a2}{2}=\dfrac{194}{2}\\\\\Rightarrow \dfrac{a1+a2}{2}=97.[/tex]

Thus, the average of the first two test scores is 97.

Answer:

Thus, the average of the first two test scores is 97.

Step-by-step explanation:

Suppose that replacement times for washing machines are normally distributed with a mean of 9.3 years and a standard deviation of 1.1 years. Find the probability that 70 randomly selected washing machines will have a mean replacement time less than 9.1 years. Your answer should be a decimal rounded to the fourth decimal place.

Answers

Answer:

The probability is 0.0643

Step-by-step explanation:

* Lets revise some definition to solve the problem

- The standard deviation of the distribution of sample means is called σM

- σM = σ/√n , where σ is the standard deviation and n is the sample size

- z-score = (M - μ)/σM, where M is the mean of the sample , μ is the mean

 of the population  

* Lets solve the problem

- The mean of the washing machine is 9.3 years

μ = 9.3

- The standard deviation is 1.1 years

σ = 1.1

- There are 70 washing machines randomly selected

n = 70

- The mean replacement time less than 9.1 years

M = 9.1

- Lets calculate z-score

∵ σM = σ/√n

σM = 1.1/√70 = 0.1315

∵ z-score = (M - μ)/σM

z-score = (9.1 - 9.3)/0.1315 = - 1.5209

- Use the normal distribution table of z to find P(z < -1.5209)

∴ P(z < -1.5209) = 0.06426

∵ P(M < 9.1) = P(z < -1.5209)

∴ P(M < 9.1) = 0.0643

* The probability is 0.0643

A brand name has a 40​% recognition rate. If the owner of the brand wants to verify that rate by beginning with a small sample of 5 randomly selected​ consumers, find the probability that exactly 2 of the 5 consumers recognize the brand name. Also find the probability that the number who recognize the brand name is not 2.

Answers

Answer:

1) 0.3456

2) 0.6544.

Step-by-step explanation:

Let X represents the event of recognizing the brand,

Given,

The probability of recognizing the brand, p = 40​% = 0.40,

Thus, the probability of not recognizing the brand, q = 1 - 0.40 = 0.60,

Since, the binomial distribution formula,

[tex]P(x) = ^nC_r (p)^r(q)^{n-r}[/tex]

Where,

[tex]^nC_r=\frac{n!}{r!(n-r)!}[/tex]

1) Thus, the probability that exactly 2 of the 5 consumers recognize the brand name is,

[tex]P(X=2)=^5C_2 (0.40)^2 (0.60)^{5-2}[/tex]

[tex]=10 (0.40)^2 (0.60)^3[/tex]

[tex]=0.3456[/tex]

2) Also, the probability that the number who recognize the brand name is not 2 = 1 - P(X=2) = 1 - 0.3456 = 0.6544.

Doing research for insurance rates, it is found that those aged 30 to 49 drive an average of 38.7 miles per day with a standard deviation of 6.7 miles. These distances are normally distributed. If a group of 60 drivers in that age group are randomly selected, what is the probability that the mean distance traveled each day is between 32.5 miles and 40.5 miles?

Answers

Answer: 0.4302

Step-by-step explanation:

Given : Mean : [tex]\mu=\text{38.7 miles }[/tex]

Standard deviation : [tex]\sigma=\text{6.7 miles }[/tex]

Sample size : [tex]n=60[/tex]

Also, these distances are normally distributed.

Then , the formula to calculate the z-score is given by :-

[tex]z=\dfrac{x-\mu}{\sigma}[/tex]

For x=32.5

[tex]\\\\ z=\dfrac{32.5-38.7}{6.7}=-0.925373134\approx-0.93[/tex]

For x=40.5

[tex]\\\\ z=\dfrac{40.5-38.7}{6.7}=0.268656\approx0.27[/tex]

The p-value = [tex]P(-0.93<z<0.27)[/tex]

[tex]=P(0.27)-P(-0.93)=0.6064198- 0.1761855=0.4302343\approx0.4302[/tex]

Hence, the required probability :-0.4302


I need the answer to this question.

1) Divide 704 days 11 hours by 29.

Answers

There are 24 hours to a day, so you can write this as

704 days, 11 hours = 704 + 11/24 days

Then dividing by 29 gives

704/29 + 11/696 days

We have

704 = 24*29 + 8

so that the time is equal to

24 + 8/29 + 11/696 days

24 + (192 + 11)/696 days

24 + 7/24 days

which in terms of days and hours is

24 days, 7 hours

The U.S. Center for Disease Control reports that the mean life expectancy was 47.6 years for whites born in 1900 and 33.0 years for nonwhites. Suppose that you randomly survey death records for people born in 1900 in a certain county. Of the 124 whites, the mean life span was 45.3 years with a standard deviation of 12.7 years. Of the 82 nonwhites, the mean life span was 34.1 years with a standard deviation of 15.6 years. Conduct a hypothesis test to see if the mean life spans in the county were the same for whites and nonwhites.

Answers

The correct option is to reject the null hypothesis. The mean life spans for whites and non-whites born in 1900 in the certain county are not the same.

To conduct the hypothesis test, we will use a two-sample z-test for the difference in two means. The null hypothesis (H0) states that there is no difference in the mean life spans between whites and non-whites, while the alternative hypothesis (Ha) states that there is a difference.

The formula for the z-test statistic is:

[tex]\[ z = \frac{(\bar{x}_1 - \bar{x}_2) - (\mu_1 - \mu_2)}{\sqrt{\frac{\sigma_1^2}{n_1} + \frac{\sigma_2^2}{n_2}}} \][/tex]

where:

- [tex]\(\bar{x}_1\)[/tex] and [tex]\(\bar{x}_2\)[/tex] are the sample means for whites and non-whites, respectively.

- [tex]\(\mu_1\)[/tex] and [tex]\(\mu_2\)[/tex] are the population means for whites and non-whites, respectively.

- [tex]\(\sigma_1\)[/tex] and [tex]\(\sigma_2\)[/tex] are the population standard deviations for whites and non-whites, respectively.

- [tex]\(n_1\)[/tex] and [tex]\(n_2\)[/tex] are the sample sizes for whites and non-whites, respectively.

Given:

- [tex]\(\bar{x}_1 = 45.3\) years, \(s_1 = 12.7\) years, \(n_1 = 124\)[/tex] (for whites)

- [tex]\(\bar{x}_2 = 34.1\)[/tex] years, [tex]\(s_2 = 15.6\) years, \(n_2 = 82\)[/tex] (for non-whites)

- [tex]\(\mu_1 = 47.6\)[/tex] years (for whites)

- [tex]\(\mu_2 = 33.0\)[/tex] years (for non-whites)

Since we do not have the population standard deviations, we will use the sample standard deviations as an estimate. This is appropriate given the sample sizes are large enough (generally [tex]\(n > 30\)[/tex] is considered sufficient).

First, we calculate the standard error (SE) of the difference in means:

[tex]\[ SE = \sqrt{\frac{s_1^2}{n_1} + \frac{s_2^2}{n_2}} = \sqrt{\frac{12.7^2}{124} + \frac{15.6^2}{82}} \][/tex]

[tex]\[ SE = \sqrt{\frac{161.29}{124} + \frac{243.36}{82}} \][/tex]

[tex]\[ SE = \sqrt{1.299 + 2.968} \][/tex]

[tex]\[ SE = \sqrt{4.267} \][/tex]

[tex]\[ SE \approx 2.066 \][/tex]

Now, we calculate the z-statistic:

[tex]\[ z = \frac{(45.3 - 34.1) - (47.6 - 33.0)}{2.066} \][/tex]

[tex]\[ z = \frac{11.2 - 14.6}{2.066} \][/tex]

[tex]\[ z = \frac{-3.4}{2.066} \][/tex]

[tex]\[ z \approx -1.646 \][/tex]

Next, we find the p-value for this z-statistic. Since we are conducting a two-tailed test, we will look at the probability of a z-score being less than -1.646 or greater than 1.646. Using a standard normal distribution table or a calculator, we find that the p-value is approximately 0.100.

Finally, we compare the p-value to our significance level (commonly denoted as [tex]\(\alpha\))[/tex]. If the p-value is less than [tex]\(\alpha\)[/tex], we reject the null hypothesis. If we choose [tex]\(\alpha = 0.05\)[/tex], then since [tex]\(0.100 > 0.05\)[/tex], we fail to reject the null hypothesis.

However, if we choose a significance level of [tex]\(\alpha = 0.10\)[/tex], then since [tex]\(0.100 \leq 0.10\)[/tex], we would reject the null hypothesis, indicating that there is a statistically significant difference in the mean life spans between whites and non-whites in the county.

Given the p-value is on the boundary of common significance levels, the conclusion may vary depending on the chosen level of significance. However, the correct option based on the provided conversation is to reject the null hypothesis, suggesting that the mean life spans are not the same for whites and non-whites in the county.

A company that makes cola drinks states that the mean caffeine content per​ 12-ounce bottle of cola is 40 milligrams. You want to test this claim. During your​ tests, you find that a random sample of thirty​ 12-ounce bottles of cola has a mean caffeine content of 42.3 milligrams. Assume the population is normally distributed and the population standard deviation is 7.1 milligrams. At alphaequals0.04​, can you reject the​ company's claim

Answers

Answer:

Step-by-step explanation:

Put hypotheses as:

[tex]H_0: mu =40 mg\\H_a: mu \neq 40 mg.[/tex]

(Two tailed test at 4%)

Since population std deviation is  given we can do Z test.

[tex]Sample size n =30\\Sample mean = 42.3 mg\\Mean diff = 2.3 mg\\Std error of sample = \frac{7.1}{\sqrt{30} } =1.296[/tex]

Test statistic t = mean diff/se = [tex]\frac{2.3}{1.296} =1.775[/tex]

p value=0.075

Since p >0.04 our alpha, we accept null hypothesis.

At alphaequals0.04​, we cannot reject the​ company's claim

Step-by-step explanation:

Put hypotheses as:

\begin{gathered}H_0: mu =40 mg\\H_a: mu \neq 40 mg.\end{gathered}

H

0

:mu=40mg

H

a

:mu

=40mg.

(Two tailed test at 4%)

Since population std deviation is given we can do Z test.

\begin{gathered}Sample size n =30\\Sample mean = 42.3 mg\\Mean diff = 2.3 mg\\Std error of sample = \frac{7.1}{\sqrt{30} } =1.296\end{gathered}

Samplesizen=30

Samplemean=42.3mg

Meandiff=2.3mg

Stderrorofsample=

30

7.1

=1.296

Test statistic t = mean diff/se = \frac{2.3}{1.296} =1.775

1.296

2.3

=1.775

p value=0.075

Since p >0.04 our alpha, we accept null hypothesis.

At alphaequals0.04, we cannot reject the company's claim

A tank holds 300 gallons of water and 100 pounds of salt. A saline solution with concentration 1 lb salt/gal is added at a rate of 4 gal/min. Simultaneously, the tank is emptying at a rate of 1 gal/min. Find the specific solution Q(t) for the quantity of salt in the tank at a given time t.

Answers

The amount of salt in the tank changes with rate according to

[tex]Q'(t)=\left(1\dfrac{\rm lb}{\rm gal}\right)\left(4\dfrac{\rm gal}{\rm min}\right)-\left(\dfrac{Q(t)}{300+(4-1)t}\dfrac{\rm lb}{\rm gal}\right)\left(1\dfrac{\rm gal}{\rm min}\right)[/tex]

[tex]\implies Q'+\dfrac Q{300+3t}=4[/tex]

which is a linear ODE in [tex]Q(t)[/tex]. Multiplying both sides by [tex](300+3t)^{1/3}[/tex] gives

[tex](300+3t)^{1/3}Q'+(300+3t)^{-2/3}Q=4(300+3t)^{1/3}[/tex]

so that the left side condenses into the derivative of a product,

[tex]\big((300+3t)^{1/3}Q\big)'=4(300+3t)^{1/3}[/tex]

Integrate both sides and solve for [tex]Q(t)[/tex] to get

[tex](300+3t)^{1/3}Q=(300+3t)^{4/3}+C[/tex]

[tex]\implies Q(t)=300+3t+C(300+3t)^{-1/3}[/tex]

Given that [tex]Q(0)=100[/tex], we find

[tex]100=300+C\cdot300^{-1/3}\implies C=-200\cdot300^{1/3}[/tex]

and we get the particular solution

[tex]Q(t)=300+3t-200\cdot300^{1/3}(300+3t)^{-1/3}[/tex]

[tex]\boxed{Q(t)=300+3t-2\cdot100^{4/3}(100+t)^{-1/3}}[/tex]

Find the equation of the following line and graph. Through (3,-10) perpendicular to 5x-y=9

Answers

bearing in mind that perpendicular lines have negative reciprocal slopes, let's find the slope of 5x -  y = 9 then.

[tex]\bf 5x-y=9\implies -y=-5x+9\implies y=\stackrel{\stackrel{m}{\downarrow }}{5}x-9\leftarrow \begin{array}{|c|ll} \cline{1-1} slope-intercept~form\\ \cline{1-1} \\ y=\underset{y-intercept}{\stackrel{slope\qquad }{\stackrel{\downarrow }{m}x+\underset{\uparrow }{b}}} \\\\ \cline{1-1} \end{array} \\\\[-0.35em] ~\dotfill[/tex]

[tex]\bf \stackrel{\textit{perpendicular lines have \underline{negative reciprocal} slopes}} {\stackrel{slope}{5\implies \cfrac{5}{1}}\qquad \qquad \qquad \stackrel{reciprocal}{\cfrac{1}{5}}\qquad \stackrel{negative~reciprocal}{-\cfrac{1}{5}}}[/tex]

so then, we're really looking for the equation of a line whose slope is -1/5 and runs through (3,-10).

[tex]\bf (\stackrel{x_1}{3}~,~\stackrel{y_1}{-10})~\hspace{10em} slope = m\implies -\cfrac{1}{5} \\\\\\ \begin{array}{|c|ll} \cline{1-1} \textit{point-slope form}\\ \cline{1-1} \\ y-y_1=m(x-x_1) \\\\ \cline{1-1} \end{array}\implies y-(-10)=-\cfrac{1}{5}(x-3)\implies y+10=-\cfrac{1}{5}x+\cfrac{3}{5} \\\\\\ y=-\cfrac{1}{5}x+\cfrac{3}{5}-10\implies y=-\cfrac{1}{5}x+\cfrac{53}{5}[/tex]

and it looks like the one in the picture below.

Round each of the following, using front-end rounding. [1.1] 4. 50,987 5. 851,004

Answers

Answer:

4) 50,000

5) 900,000

Step-by-step explanation:

In Front end rounding what we do is we focus on first two digit of the number if the second digit number is greater than or equal to 5 we add the first digit by 1.

4) 50,987

here we can clearly see that the first two digit is 50 and second digit is not equal to 5 then rounding will be equal to 50,000.

5) 851,004

here we can clearly see that the first two digit is 85 and second digit is equal to 5 then we will round it  8+1=9

hence rounded number will be 900,000

Final answer:

Front-end rounding of 50,987 is 50,000 and for 851,004 it's 900,000, based on the most significant digits, using zeros as placeholders after rounding.

Explanation:

Front-end rounding involves rounding numbers based on the most significant digits. Let's apply this method to the numbers provided.

50,987 rounded to the nearest ten thousand would be 50,000.For 851,004, rounded to the nearest hundred thousand would be 900,000.

When rounding, if the digit immediately after the place you are rounding to is 5 or greater, you round up. Otherwise, you round down. Placeholder zeros are used to maintain the value's place in the number system.

Suppose consumers will demand 40 units of a product when the price is $12 per unit and 25 units when the price is $18 each. Find the demand equation assuming that it is linear. Find the price per unit when 30 units are demanded.

Answers

Answer: The price per unit is $48, when 30 units are demanded.

Step-by-step explanation:

Since we have given that

At price of $12 per unit, the number of units demanded = 40 units

At price of $18 per unit, the number of units demanded = 25 units.

So, the coordinates would be

(40,12) and (25,18)

As we know that x- axis denoted the quantity demanded.

y-axis denoted the price per unit.

So, the slope would be

[tex]m=\dfrac{y_2-y_1}{x_2-x_1}\\\\m=\dfrac{18-12}{25-40}\\\\m=\dfrac{-6}{15}\\\\m=\dfrac{-2}{5}[/tex]

So, the equation would be

[tex]y-y_1=m(x-x_1)\\\\y-12=\dfrac{-2}{5}(x-40)\\\\5(y-12)=-2(x-40)\\\\5y-60=-2x+80\\\\5y+2x=80+60\\\\5y+2x=140[/tex]

So, if 30 units are demanded, the price per unit would be

[tex]5y=140+2x\\\\5y=140+2\times 30\\\\5y=140+60\\\\5y=240\\\\y=\dfrac{240}{5}\\\\y=\$48[/tex]

Hence, the price per unit is $48, when 30 units are demanded.

Final answer:

The linear demand equation is Qd = 100 - 5P. In this equation, if we want to find the price per unit when 30 units are demanded, substitute Qd with 30 to get P = 14.

Explanation:

To find the linear demand equation, we can use the data given: consumers will buy 40 units of a product when the price is $12 per unit and 25 units when the price is $18 per unit. The general formula for a linear demand equation is Qd = a - bP, where Qd is the quantity demanded, P is the price per unit, a is the intercept, and b is the slope of the demand curve.

Let's use the two points (12, 40) and (18, 25) to formulate two equations with a and b as unknowns. We find that a = 100 and b = 5, therefore the demand equation is Qd = 100 - 5P. Now if we want to find the price per unit when 30 units are demanded, we just need to substitute Qd with 30 in the demand equation, hence P = 14.

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4.D.15 Consider a student loan of $17,500 at a fixed APR of 6% for 25 years. a. Calculate the monthly payment. b. Determine the total amount paid over the term of the loan. c. Of the total amount paid, what percentage is paid toward the principal and what percentage is paid for interest a. The monthly payment is $ (Do not round until the final answer. Then round to the nearest cent as needed.) ess ibrary

Answers

Final answer:

The monthly payment for a $17,500 loan at 6% APR over 25 years is about $113.36. The total amount paid over the duration of the loan is $34,008, of which about 51.46% goes towards the principal and 48.54% towards interest.

Explanation:

To answer this question, we need to use the formula for calculating the monthly payment for a loan, which is P[r(1 + r)^n]/[(1 + r)^n - 1], where P is the principal loan amount, r is the monthly interest rate (annual rate divided by 12), and n is the number of payments (years times 12).

a. Monthly payment:

First, we have to calculate r: 6% APR implies a yearly interest rate of 6%/12 = 0.005 per month. Plugging P = $17,500, r = 0.005, and n = 25*12 = 300 into the formula, we get the monthly payment of approximately $113.36.

b. Total amount paid:

The total amount paid over the duration of the loan is simply the monthly payment times the total number of payments, so $113.36*300 = $34,008.

c. Percentages of principal and interest:

The percentage paid towards the principal is the original loan amount divided by the total payment amount times 100, so $17,500/$34,008*100 = approximately 51.46%. Therefore, the percentage paid for interest is 100 - 51.46 = 48.54%.

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The monthly payment for the loan is approximately $114.08. Over 25 years, the total amount paid will be about $34,224. About 51.11% of this amount goes toward the principal and 48.89% goes toward interest.

To solve this problem, we need to calculate the monthly payment, total amount paid, and the percentages of principal and interest paid for a student loan of $17,500 at a fixed APR of 6% for 25 years.

a. Calculate the monthly payment

We use the formula for the monthly payment on an amortizing loan:

→ [tex]M = P [r(1 + r)^n] / [(1 + r)^{n - 1}][/tex]

where:

→ P = loan principal ($17,500)

→ r = monthly interest rate (annual rate / 12)

    = 6% / 12

    = 0.005

→ n = total number of payments (years * 12)

     = 25 * 12

     = 300

Substituting the values into the formula:

→ [tex]M = 17500 [0.005(1 + 0.005)^{300}] / [(1 + 0.005)^{300 – 1}][/tex]

→ M = 17500 [0.005(4.2918707)] / [4.2918707 – 1]

→ M = 17500 [0.02145935] / [3.2918707]

→ M = 375.53965 / 3.2918707

→ M ≈ $114.08

b. Determine the total amount paid over the term of the loan

→ Total amount paid = monthly payment * total number of payments

→ Total amount paid = 114.08 * 300

                                 ≈ $34,224

c. Of the total amount paid, what percentage is paid toward the principal and what percentage is paid for interest

→ Principal: $17,500

→ Interest: Total amount paid - Principal

→ Interest = 34,224 - 17,500

                ≈ $16,724

→ Percentage toward principal = (Principal / Total amount paid) * 100

                                                   ≈ (17500 / 34224) * 100

                                                   ≈ 51.11%

→ Percentage toward interest = (Interest / Total amount paid) * 100

                                                 ≈ (16724 / 34224) * 100

                                                 ≈ 48.89%

Approximate the number below using a calculator. Round your answer to three decimal places. el.3 a) 3.534 b) 3.669 c) 3.969 d) 2.040

Answers

Answer:

a. 3.53 b. 3.61 c. 3.91 d. 2.04

Step-by-step explanation:

a. 3.534 take 4 out

b. 3.669 nine is higher then 5 so, take six makes out of one

c. 3.969 nine is higher then 5 so, take six makes out of one

d. 2.040 take zero out

above that is the answer.... hope i helped this....

Prove that the set of all odd positive integers is countable.

Answers

Answer:

See below.

Step-by-step explanation:

The set of  all positive integers N is countable so we need to show that there is a 1 to 1 correspondence between the elements in N  with the set of all odd positive integers. This is the case as shown below:

1 2 3 4 5 6 ...

|  |  |   |   |  | ....

1 3 5 7 9 11....

4x^2 y+8xy'+y=x, y(1)= 9, y'(1)=25

Answers

Answer with explanation:

[tex]\rightarrow 4x^2y+8x y'+y=x\\\\\rightarrow 8xy'+y(1+4x^2)=x\\\\\rightarrow y'+y\times\frac{1+4x^2}{8x}=\frac{1}{8}[/tex]

--------------------------------------------------------Dividing both sides by 8 x

This Integration is of the form ⇒y'+p y=q,which is Linear differential equation.

Integrating Factor

 [tex]=e^{\int \frac{1+4x^2}{8x} dx}\\\\e^{\log x^{\frac{1}{8}+\frac{x^2}{2}}\\\\=x^{\frac{1}{8}}\times e^{\frac{x^2}{2}}[/tex]

Multiplying both sides by Integrating Factor  

[tex]x^{\frac{1}{8}}\times e^{\frac{x^2}{2}}\times [y'+y\times\frac{1+4x^2}{8x}]=\frac{1}{8}\times x^{\frac{1}{8}}\times e^{\frac{x^2}{2}}\\\\ \text{Integrating both sides}\\\\y\times x^{\frac{1}{8}}\times e^{\frac{x^2}{2}}=\frac{1}{8}\int {x^{\frac{1}{8}}\times e^{\frac{x^2}{2}}} \, dx \\\\8y\times x^{\frac{1}{8}}\times e^{\frac{x^2}{2}}=\int {x^{\frac{1}{8}}\times e^{\frac{x^2}{2}}} \, dx\\\\8y\times x^{\frac{1}{8}}\times e^{\frac{x^2}{2}}=-[x^{\frac{9}{8}}]\times\frac{ \Gamma(0.5625, -x^2)}{(-x^2)^{\frac{9}{16}}}\\\\8y\times x^{\frac{1}{8}}\times e^{\frac{x^2}{2}}=(-1)^{\frac{-1}{8}}[ \Gamma(0.5625, -x^2)]+C-----(1)[/tex]

When , x=1, gives , y=9.

Evaluate the value of C and substitute in the equation 1.

Jayanta is raising money for the​ homeless, and discovers each church group requires 2 hr of letter writing and 1 hr of​ follow-up calls, while each labor union needs 2 hr of letter writing and 3 hr of ​follow-up. She can raise ​$125 from each church group and ​$175 from each union. She has a maximum of 20 hours of letter writing and 14 hours of ​follow-up available each month. Determine the most profitable mixture of groups she should contact and the most money she can raise in a month.

Answers

Answer:

8 churches, 2 unions; $1350 per month

Step-by-step explanation:

Let x and y represent the numbers of churches and unions contacted in the month, respectively. Then Jayanta's limit on letter writing hours is ...

  2x +2y ≤ 20

and her limit on follow-up call hours is ...

  x + 3y ≤ 14

Graphing these inequalities (see below) results in a feasible region with vertices at (x, y) = (0, 4 2/3), (8, 2), and (10, 0). Of these, the mixture of groups producing the most money is ...

  8 churches and 2 unions.

The money she can raise from that mixture is ...

  8×$125 +2×$175 = $1350 in a month

Answer:

Sqdancefan's answer is correct.

Step-by-step explanation:

I  misread the question.

For f(x) = 2|x+3| – 5, name the type of function and describe each of the three
transformations from the parent function f(x) = |x|

Answers

Type of function: Absolute value function
Transformation 1: Stretch vertically by a factor of 2
Transformation 2: Translate left by 3 units
Transformation 3: Translate down by 5 units

Answer:

There are three transformation i.e. vertically stretch, downward and towards left.            

Step-by-step explanation:

Given : Parent function [tex]f(x)=|x|[/tex] and transformed function [tex]f(x)=2|x+3|-5[/tex]

To find : Name the type of function and describe each of the three transformations?

Solution :

Parent function [tex]f(x)=|x|[/tex] get transformed into [tex]f(x)=2|x+3|-5[/tex]

The transformations are as follow :

1) The function is multiplied by 2 which means there is a transformation vertically by a stretch factor '2'.

2) The function is subtracted by 5 which means there is a transformation downward by a factor '5'.

3) The function inside x value get added by 3 which means there is a transformation left by a factor '3'.

Therefore, There are three transformation i.e. vertically stretch, downward and towards left.

If f(x) = 2x - 1 and g(x) = x^2 - 2, find [g · f](x)

please show me how to do this

Answers

Answer:

(x² -7)/(2x + 1)

Step-by-step explanation:

f(x) = 2x+1 and g(x) = x² -7

thus: (g/f)(x) = g(x)/f(x) = x² -7/2x + 1

Hello!

The answer is:

[tex](g \circ f)(x)=4x^{2}-4x-1[/tex]

Why?

To solve the problem, we need to remember that composing functions means evaluate a function into another different function.

Also, we need to remember how to solve the following notable product:

[tex](a-b)^{2}=a^{2}-2ab+b^{2}[/tex]

We have that:

[tex](g \circ f)(x)=g(f(x))[/tex]

Now, we are given the equations:

[tex]f(x)=2x-1\\g(x)=x^{2}-2[/tex]

So, composing we have:

[tex](g \circ f)(x)=g(f(x))[/tex]

[tex](g \circ f)(x)=(2x-1)^{2}-2[/tex]

Now, we have to solve the notable product:

[tex](g \circ f)(x)=((2x)^{2}-2(2x*1)+1^{2})-2[/tex]

[tex](g \circ f)(x)=4x^{2}-4x+1-2[/tex]

Hence, we have that:

[tex](g \circ f)(x)=4x^{2}-4x-1[/tex]

Have a nice day!

Raul received a score of 77 on a history test for which the class mean was 70 with a standard deviation of 6. He received a score of 79 on a biology test for which the class mean was 70 with standard deviation 4. On which test did he do better relative to the rest of the class?

Answers

Answer:

He did better on biology test.

Step-by-step explanation:

For comparing the scores we need to find z-scores for both subjects,

We know that,

z-score or standard score for x is,

[tex]z=\frac{x-\mu}{\sigma}[/tex]

Where, [tex]\mu[/tex] is mean,

[tex]\sigma[/tex] is standard deviation,

In history test,

[tex]x=77[/tex]

[tex]\mu=70[/tex]

[tex]\sigma = 6[/tex]

Thus, the z-score would be,

[tex]z_1=\frac{77-70}{6}[/tex]

[tex]\approx 1.167[/tex]

In biology test,

[tex]x=79[/tex]

[tex]\mu = 70[/tex]

[tex]\sigma = 4[/tex],

Thus, the z-score would be,

[tex]z_2=\frac{79-70}{4}[/tex]

[tex]= 2.25[/tex]

∵ [tex]z_2>z_1[/tex]

Hence, he did better on biology test.

.3 3. True or False? For any integer m, 2m(3m + 2) is divisible by 4. Explain to get credit.

Answers

Answer with explanation:

We have to prove that, For any integer m, 2 m×(3 m + 2) is divisible by 4.

We will prove this result with the help of Mathematical Induction.

⇒For Positive Integers

For, m=1

L HS=2×1×(3×1+2)

      =2×(5)

       =10

It is not divisible by 4.

⇒For Negative Integers

For, m= -1

L HS=2×(-1)×[3×(-1)+2]

      =-2×(-3+2)

       = (-2)× (-1)

       =2

It is not divisible by 4.

False Statement.

3. Let U and V be subspaces of a vector space W. Prove that their intersection UnV is also a subspace of W

Answers

Answer:  The proof is done below.

Step-by-step explanation:  Given that U and V are subspaces of a vector space W.

We are to prove that the intersection U ∩ V is also a subspace of W.

(a) Since U and V are subspaces of the vector space W, so we must have

0 ∈ U and 0 ∈ V.

Then, 0 ∈ U ∩ V.

That is, zero vector is in the intersection of U and V.

(b) Now, let x, y ∈ U ∩ V.

This implies that x ∈ U, x ∈ V, y ∈ U and y ∈ V.

Since U and V are subspaces of U and V, so we get

x + y ∈ U  and  x + y ∈ V.

This implies that x + y ∈ U ∩ V.

(c) Also, for a ∈ R (a real number), we have

ax ∈ U and ax ∈ V (since U and V are subspaces of W).

So, ax ∈ U∩ V.

Therefore, 0 ∈ U ∩ V and for x, y ∈ U ∩ V, a ∈ R, we have

x + y and ax ∈ U ∩ V.

Thus, U ∩ V is also a subspace of W.

Hence proved.

Consider the region satisfying the inequalities.y ≤ e−x, y ≥ 0, x ≥ 0a) Find area of regionb) Find the volume of the solid generated by revolving the region about the x-axis.c) Find the volume of the solid generated by revolving the region about the y-axis.

Answers

Revolving about the [tex]x[/tex]-axis:

Using the disk method, the volume is

[tex]\displaystyle\pi\int_0^\infty e^{-2x}\,\mathrm dx=\boxed{\frac\pi2}[/tex]

Alternatively, using the shell method, the volume is

[tex]\displaystyle2\pi\int_0^1y(-\ln y)\,\mathrm dy=\frac\pi2[/tex]

Revolving about the [tex]y[/tex]-axis:

Using the shell method, the volume is

[tex]\displaystyle2\pi\int_0^\infty xe^{-x}\,\mathrm dx=\boxed{2\pi}[/tex]

Alternatively, using the disk method, the volume is

[tex]\displaystyle\pi\int_0^1(-\ln x)^2\,\mathrm dx=2\pi[/tex]

Final answer:

The area of the region is 1 square unit. The volume of the solid generated by revolving the region about the x-axis can be found by integrating π(y^2) dx from x = 0 to x = ∞.

Explanation:

To find the area of the region, we need to find the intersection points between the two curves. In this case, the curves are y = e^(-x) and y = 0. Since y ≥ 0, the region will lie between the x-axis and the curve y = e^(-x). The intersection point is where y = 0, which occurs at x = 0. To find the area, we integrate y = e^(-x) from x = 0 to x = ∞:

A = ∫0∞ e^(-x) dx = [-e^(-x)]0∞ = -[e^0 - 0]
               = -[1 - 0] = 1

The area of the region is 1 square unit.

To find the volume of the solid generated by revolving the region about the x-axis, we use the disk method. The radius of each disk is given by y = e^(-x), and the height of each disk is given by dx. The volume can be found by integrating π(y^2) dx from x = 0 to x = ∞:

V = π∫0∞ (e^(-x))^2 dx = π∫0∞ e^(-2x) dx

PLEASE HELP PRECALCULUS WILL MARK BRAINLIEST

Answers

Answer:

[tex]\dfrac{21\pi}{10},\ -\dfrac{19\pi}{10}[/tex]

Step-by-step explanation:

Any of the angles (in radians) π/10 +2kπ (k any integer) will be co-terminal with π/10. The angles listed in the answer above have k=1, k=-1.

_____

Comment on the last answer choice

The answer choices π/10+360° and π/10-360° amount to the same thing as the answer shown above, but use mixed measures. 1 degree is π/180 radians, so 360° is 2π radians. Then π/10+360° is fully equivalent to 21π/10 radians.

Assuming that in a box there are 10 black socks and 12 blue socks, calculate the maximum number of socks needed to be drawn from the box before a pair of the same color can be made. Using the pigeonhole principle

Answers

Answer:

Step-by-step explanation:

The pigeonhole principal states that if n items are put into m containers, with n > m then at least one container must contain more than one item.

In other words, to find the case where maximum attempts are required, we eliminate all the cases where our criterion is not met and we will be left with the desired result.

For this case, the box has 10 black socks and 12 blue socks.

10 black socks = 5 left foot ones and  5 right foot ones

12 blue socks = 6 left foot ones and 6 right foot ones

If we draw all left foot or right foot ones then we will not have a pair till 11 draws have been made.

The next socks drawn will be a right foot one of blue or black color and a pair will be made.

Therefore, the maximum number of socks needed to be drawn from the box are 12.

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