A cottage industry exists in the home-manufacture of 'country crafts'. Especially treasured are handmade quilts. If the fourth completed quilt took 40 hours to make, and the eighth quilt took 35 hours. What is the percentage learning

Answer:

The volume of the resulting solid is π/2 cubic units.

Step-by-step explanation:

Please refer to the diagram below.

The shell method is given by:

[tex]\displaystyle V = 2\pi \int _a ^b r(x) h(x)\, dx[/tex]

Where the representative rectangle is parallel to the axis of revolution, r(x) is the distance from the axis of revolution to the center of the rectangle, and h(x) is the height of the rectangle.

From the diagram, we can see that r(x) = (2 - x) and that h(x) is simply y. The limits of integration are from a = 0 to b = 1. Therefore:

[tex]\displaystyle V = 2\pi \int_0^1\underbrace{\left(2-x\right)}_{r(x)}\underbrace{\left(x - x^2\right)}_{h(x)}\, dx[/tex]

Evaluate:

[tex]\displaystyle \begin{aligned} V&= 2\pi \int_0 ^1 \left(2x-2x^2-x^2+x^3\right) \, dx\\ \\ &= 2\pi\int _0^1 x^3 -3x^2 + 2x \, dx \\ \\ &= 2\pi\left(\frac{x^4}{4} - x^3 + x^2 \Bigg|_0^1\right) \\ \\ &= 2\pi \left(\frac{1}{4} - 1 + 1 \right) \\ \\ &= \frac{\pi}{2}\end{aligned}[/tex]

The volume of the resulting solid is π/2 cubic units.

Answer:

pi/2

Step-by-step explanation:

I always like to draw an illustration for these problems.

For shells method think volume of cylinder=2pi×r×h

Integrate(2pi(2-x)(x-x^2) ,x=0...1)

Multiply

Integrate(2pi(2x-2x^2-x^2+x^3 ,x=0...1)

Combine like terms

Integrate(2pi(2x-3x^2+x^3) ,x=0...1)

Begin to evaluate

2pi(2x^2/2-3x^3/3+x^4/4) ,x=0...1

2pi(x^2-x^3+x^4/4), x=0...1

2pi(1-1+1/4)

2pi/4

pi/2

Answer:

40

Step-by-step explanation:

2x² - 5y + 7 when x = 2 and y = -5

2(2)² - 5(-5) + 7

= 2(4) -5(-5) + 7

= 8 + 25 + 7

= 40

Answer:

11 meters

Step-by-step explanation:

First, we can say that the square has a side length of x. The perimeter of the square is 4x, and that is how much wire goes into the square. To maximize the area, we should use all the wire possible, so the remaining wire goes into the triangle, or (11-4x).

The area of the square is x², and the area of an equilateral triangle with side length a is (√3/4)a². Next, 11-4x is equal to the perimeter of the triangle, and since it is equilateral, each side has (11-4x)/3 length. Plugging that in for a, we get the area of the equilateral triangle is

(√3/4)((11-4x)/3)²

= (√3/4)(11/3 - 4x/3)²

= (√3/4)(121/9  - 88x/9 + 16x²/9)

= (16√3/36)x² - (88√3/36)x + (121√3/36)

The total area is then

(16√3/36)x² - (88√3/36)x + (121√3/36) + x²

= (16√3/36 + 1)x² -  (88√3/36)x + (121√3/36)

Because the coefficient for x² is positive, the parabola would open up and the derivative of the parabola would be the local minimum. Therefore, to find the maximum area, we need to go to the absolute minimum/maximum points of x (x=0 or x=2.75)

When x=0, each side of the triangle is 11/3 meters long and its area is

(√3/4)a² ≈ 5.82

When x=2.75, each side of the square is 2.75 meters long and its area is

2.75² = 7.5625

Therefore, a maximum is reached when x=2.75, or the wire used for the square is 2.75 * 4 = 11 meters

The length of the square must be 4 m in order to maximize the total area.

When we put the differentiation of the given function as zero and find the value of the variable we get maxima and minima.

We have,

Length of the wire = 11 m

Let the length of the wire bent into a square = x.

The length of the wire bent into an equilateral triangle = (11 - x)

Now,

The perimeter of a square = 4 side

4 side = x

side = x/4

The perimeter of an equilateral triangle = 3 side

11 - x = 3 side

side = (11 - x)/3

Area of square = side²

Area of equilateral triangle = (√3/4) side²

Total area:

T = (x/4)² + √3/4 {(11 -x)/3}² _____(1)

Now,

To find the maximum we will differentiate (1)

dT/dx = 0

2x/4 + (√3/4) x 2(11 - x)/3 x -1 = 0

2x / 4 - (√3/4) x 2(11 - x)/3 = 0

2x/4 - (√3/6)(11 - x) = 0

2x / 4 = (√3/6)(11 - x)

√3x = 11 - x

√3x + x = 11

x (√3 + 1) = 11

x = 11 / (1.732 + 1)

x = 11/2.732

x = 4

Thus,

The length of the square must be 4 m in order to maximize the total area.

Learn more about maxima and minima here:

https://brainly.com/question/13178975

#SPJ5

Answer:

g

Step-by-step explanation:

f

Answer:

4/27

Step-by-step explanation:

total number of marbles=9

probability of red=4/9

since you returned the first marble, the total number of marbles remains the same

prob(Blue)=(3/9)=1/3

P(red then blue)=(4/9)*(1/3)

=4/27

Answer:

~~314.16

Step-by-step explanation:

lol i dont have 100000000 points. anyways

you can find the area of a sphere with the formula 4πr^2 with r being the radius

this sphere's radius is 5 as shown in the image

so

4π*r^2

4π*(5)^2

=4π*25

=100π

put into calculator

~~314.16cm^3

hope this helps

Answer:

..... surface area = 16 km^2.

Answer:

Step-by-step explanation:

Prime factorize 27 and 16

27 = 3 * 3 * 3

16 = 2 * 2 * 2 * 2

[tex]\frac{\sqrt{27}}{\sqrt{16}}=\frac{\sqrt{3*3*3}}{\sqrt{2*2*2*2}}[/tex]

     [tex]= \frac{3\sqrt{3}}{2*2}\\\\\\=\frac{3\sqrt{3}}{4}[/tex]

Answer: (3√3)/4

Explanation:

√(27/16)

=(3√3)/4

Because 27 = 3²×3

And 16 = 4²

So 4 is left and one 3 goes out and one stays in

Please click thanks and mark brainliest if you like

Perimeter = Sum of all sides

Perimeter = 14cm + 8cm + 10cm + 5cm

Perimeter = 22cm + 15cm

Perimeter = 37cm

Step-by-step explanation:

hope it helps you

...

........

[tex]\boxed{\sf Slope(m)=\dfrac{y_2-y_1}{x_2-x_1}}[/tex]

[tex]\\ \sf\longmapsto m=\dfrac{7-4}{10-4}[/tex]

[tex]\\ \sf\longmapsto m=\dfrac{3}{6}[/tex]

[tex]\\ \sf\longmapsto m=\dfrac{1}{2}[/tex]

[tex]\\ \sf\longmapsto m\approx0.5[/tex]

Answer:

[tex]m=\frac{1}{2}[/tex]

Step-by-step explanation:

The slope of a line, also known as the change in the line or the ([tex]\frac{rise}{run}[/tex]) can be found using the following formula,

[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]

Where ([tex]x_1,y_1[/tex]) and ([tex]x_2,y_2[/tex]) are points on the line. Substitute the given information into the formula and solve for the slope.

[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]

Points on the line: [tex](4,4)\ \ \ (10, 7)[/tex]

[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]

[tex]m=\frac{7-4}{10-4}[/tex]

[tex]m=\frac{3}{6}[/tex]

[tex]m=\frac{1}{2}[/tex]

[tex]m=0.5[/tex]

Answer:

114 cm²

Step-by-step explanation:

Surface area of the rectangular prism,

2(wl+hl+hw)

=2×(3×8+3×8+3×3)

=2×(24+24+9)

=2×(57)

=114 cm²

Answer:

Inverses

Step-by-step explanation:

One things I could tell about the earth from this graph is that the northern and southern hemispheres are inverses because when the temp of one goes up over the months, the other goes down.

Answer:

a) The 99% CI for the true proportion of voters who prefer the Republican candidate is (0.3658, 0.6001). This means that we are 99% sure that the true population proportion of all voters who prefer the Republican candidate is (0.3658, 0.6001).

b) The upper bound of the confidence interval is above 0.5 = 50%, which meas that the candidate can be confidence of victory.

Step-by-step explanation:

Question a:

In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.

[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In which

z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].

Sample of 120 registered voters in order to predict the winner of a local election. The Democrat candidate was favored by 62 of the respondents.

So 120 - 62 = 58 favored the Republican candidate, so:

[tex]n = 120, \pi = \frac{58}{120} = 0.4833[/tex]

99% confidence level

So [tex]\alpha = 0.01[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.01}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].  

The lower limit of this interval is:

[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.4833 - 2.575\sqrt{\frac{0.4833*0.5167}{120}} = 0.3658[/tex]

The upper limit of this interval is:

[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.4833 + 2.575\sqrt{\frac{0.4833*0.5167}{120}} = 0.6001[/tex]

The 99% CI for the true proportion of voters who prefer the Republican candidate is (0.3658, 0.6001). This means that we are 99% sure that the true population proportion of all voters who prefer the Republican candidate is (0.3658, 0.6001).

b. If a candidate needs a simple majority of the votes to win the election, can the Republican candidate be confident of victory? Justify your response with an appropriate statistical argument.

The upper bound of the confidence interval is above 0.5 = 50%, which meas that the candidate can be confidence of victory.

[tex]\huge\text{Hey there!}[/tex]

[tex]\large\textsf{-12 + (-8) + 30}\\\\\large\textsf{= -12 - 8 + 30}\\\\\large\textsf{-12 - 8 = \bf -20}\\\\\large\textsf{= -20 + 30}\\\\\large\textsf{= \bf 10}\\\\\\\boxed{\boxed{\huge\text{Therefore, your ANSWER is: \textsf{10}}}}\huge\checkmark\\\\\\\\\huge\textsf{Good luck on your assignment \& enjoy your day!}[/tex]

~[tex]\frak{Amphitrite1040:)}[/tex]

Answer:

Step-by-step explanation:

(x-2)(x+4)=x^2+4x-2x-8=0=> x =2, x=0

Answer:

A

Step-by-step explanation:

Answer:

49

Step-by-step explanation:

sin(theta) = P/H

sin(28)=23/x, x=23/sin(28)=49

Answer:

I believe its  EG and NE but i might be wrong

Step-by-step explanation:

============================================================

Explanation:

Let's isolate the variable 'a' in the given inequality.

4a + 2 > 12

4a + 2-2 > 12-2

4a > 10

4a/4 > 10/4

a > 2.5

In the second step, I subtracted 2 from both sides to undo the "plus 2". In the second to last step, I divided both sides by 4 to undo the multiplication.

The solution is a > 2.5, meaning that anything larger than 2.5 will work in the original inequality.

For example, we could try a = 3 to get

4a + 2 > 12

4*3 + 2 > 12

12 + 2 > 12

14 > 12

which is true. This makes a = 3 a solution. The value a = 3.5 is a similar story, so it's also a solution.

------------

As an example of a non-solution, let's try a = 1

4a + 2 > 12

4*1 + 2 > 12

4 + 2 > 12

6 > 12

which is false. So we can see why a = 1 is not part of the solution set. You should find that a= 0.5 and a = 2.5 won't work as well for similar reasoning.

ANSWER: You can make 16 refrigerator magnets.

If you divide 10 by 5/8, you multiply by the reciprocal of 5/8 which is 8/5. You have 8/5 x 10. Cross simplify and you have 16.

Answer:

The sample size must be of 47,059,600.

Step-by-step explanation:

We have to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:

[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]

Now, we have to find z in the Z-table as such z has a p-value of [tex]1 - \alpha[/tex].

That is z with a p-value of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.

Now, find the margin of error M as such

[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]

In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.

Standard deviation:

[tex]\sigma = 3.5[/tex]

If you want the error bound E of a 95% confidence interval to be less than 0.001, how large must the sample size n be?

This is n for which M = 0.001. So

[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]

[tex]0.001 = 1.96\frac{3.5}{\sqrt{n}}[/tex]

[tex]0.001\sqrt{n} = 1.96*3.5[/tex]

[tex]\sqrt{n} = \frac{1.96*3.5}{0.001}[/tex]

[tex](\sqrt{n})^2 = (\frac{1.96*3.5}{0.001})^2[/tex]

[tex]n = 47059600[/tex]

The sample size must be of 47,059,600.

Answer:

The probability is 0.857

Step-by-step explanation:

We know that:

There is a total of 440 cars

There are 63 cars with defective turn signals

There are 39 with defective tires.

Now we want to find the probability that a randomly selected car does not have defective turn signals.

If all the cars have the same probability of being selected, this probability will be equal to the quotient between the number of cars that do not have defective turn signals and the total number of cars.

We know that the total number of cars is 440

And 63 of these have defective turn signals, then the rest don't.

440 - 63 = 377 cars do not have defective turn signals.

Then the probability is:

P = 377/440 = 0.857

Answer:

(1,-2)

Step-by-step explanation:

P(-1,2) and (x, y) -> (x + 2, y - 4). Plugging in x and y in the transformation, the transformed points are (-1+2, 2-4) = (1,-2)

Answer:

Kindly check explanation

Step-by-step explanation:

The power of a test simply gives the probability of Rejecting the Null hypothesis, H0 in a statistical analysis given that the the alternative hypothesis, H1 for the study is true. Hence, the power of a test can be referred to as the probability of a true positive outcome in an experiment.

Using this definition, a power of 90% simply means that ; there is a 90% probability that the a Pvalue less Than the α - value of an experiment is obtained if there is truly a significant difference. Hence, a 90% chance of Rejecting the Null hypothesis if truly the alternative hypothesis is true.

Answer:

46

Step-by-step explanation:

200/2 = 100, and the x coordinate that line up with the y-coordinate of 100 is 46.

--------------------------------------------------

Just a correction, the characteristic roots of the equation are [tex]y = 7[/tex] and [tex]y = -\frac{1}{2}[/tex], thus, we should test for:

[tex]y = Ae^{7x} + Be^{-\frac{x}{2}}[/tex]

--------------------------------------------------

Question a:

[tex]y = Ae^{7x} + Be^{-\frac{x}{2}}[/tex]

[tex]y^{\prime} = 7Ae^{-7x} - \frac{1}{2}Be^{-\frac{x}{2}}[/tex]

[tex]y^{\prime\prime} = 49Ae^{-7x} + \frac{1}{4}Be^{-\frac{x}{2}}[/tex]

[tex]2y^{\prime\prime} - 13y^{\prime} - 7y = 0[/tex]

[tex]2(49Ae^{-7x} + \frac{1}{4}Be^{-\frac{x}{2}}) - 13(7Ae^{-7x} - \frac{1}{2}Be^{-\frac{x}{2}}) - 7(Ae^{7x} + Be^{-\frac{x}{2}}) = 0[/tex]

[tex]98Ae^{-7x} + \frac{1}{2}Be^{\frac{x}{2}} - 91Ae^{-7x} + \frac{13}{2}e^{-\frac{x}{2}} - 7Ae^{7x} - 7Be^{-\frac{x}{2}} = 0[/tex]

[tex]98Ae^{-7x} - 91Ae^{-7x} - 7Be^{-\frac{x}{2}} + \frac{1}{2}Be^{\frac{x}{2}}  + \frac{13}{2}e^{-\frac{x}{2}} - 7Be^{-\frac{x}{2}} = 0[/tex]

[tex]0A + 0B = 0[/tex]

[tex]0 = 0[/tex], thus, we found the identity, and for each constant A and B, the following is a solution.

--------------------------------------------------

Question b:

[tex]y = Ae^{7x} + Be^{-\frac{x}{2}}[/tex]

[tex]A + B = 3 \rightarrow B = 3 - A[/tex]

--------------------------------------------------

[tex]y^{\prime} = 7Ae^{-7x} - \frac{1}{2}Be^{-\frac{x}{2}}[/tex]

[tex]7A - \frac{1}{2}B = -5[/tex]

Using [tex]B = 3 - A[/tex]

[tex]7A - \frac{3}{2} + \frac{A}{2} = -5[/tex]

[tex]\frac{14A}{2} + \frac{A}{2} = -\frac{10}{2} + \frac{3}{2}[/tex]

[tex]\frac{15A}{2} = -\frac{7}{2}[/tex]

[tex]15A = -7[/tex]

[tex]A = -\frac{7}{15}[/tex]

--------------------------------------------------

Then, B is given by:

[tex]B = 3 - A = 3 - (-\frac{7}{15}) = \frac{45}{15} + \frac{7}{15} = \frac{52}{15}[/tex]

Thus, the values are: [tex]A = -\frac{7}{15}, B = \frac{52}{15}[/tex]

A similar problem is given at https://brainly.com/question/2456414

Answer:

A and B must always be congruent

B and D

E and G

F and H

Step-by-step explanation:

I have to be honest. from the picture I cannot see the vertical angles. All I see is a straight blue line and red letters. But based on the vertical theorem

A and B must always be congruent

B and D

E and G

F and H

also if you want to make sure it's right try to include another picture.

Answer:

Step-by-step explanation:

edmentum :)