Li designed a survey to determine how comfortable students at her middle school are with fractions. There are 600 students in her middle school. The students are equally distributed among grade levels. She selected a sample of 28 students in her first-period class. Which best explains Li’s sample? random and biased random and unbiased nonrandom and biased nonrandom and unbiased.

The dimension of the container of this size that has the minimum cost is [tex]x = \sqrt[3]{360}[/tex], [tex]y = \sqrt[3]{360}[/tex] and [tex]z =\frac{4}{3} \sqrt[3]{360}[/tex]

The given parameters are:

Assume the dimensions of the container are: x, y and z.

The volume (V) would be:

[tex]V = xyz[/tex]

Substitute 480 for V

[tex]xyz =480[/tex]

And the objective cost function would be:

[tex]C =8xy + 6xz + 6yz[/tex]

Differentiate the cost function using Lagrange multipliers

[tex]8x + 6z = \lambda xz[/tex]

[tex]8y + 6z = \lambda yz[/tex]

[tex]6x + 6y = \lambda xy[/tex]

Divide equation (1) by (2)

[tex]\frac{8x + 6z}{8y + 6z} = \frac{\lambda xz}{\lambda yz}[/tex]

[tex]\frac{8x + 6z}{8y + 6z} = \frac{x}{y}[/tex]

Factor out 2

[tex]\frac{4x + 3z}{4y + 3z} = \frac{x}{y}[/tex]

Cross multiply

[tex]4xy + 3yz = 4xy + 3xz[/tex]

Evaluate the like terms

[tex]3yz = 3xz[/tex]

Divide both sides by 3z

[tex]y = x[/tex]

Divide the first equation by the third

[tex]\frac{8y + 6z}{6x + 6y} = \frac{\lambda yz}{\lambda xy}[/tex]

[tex]\frac{8y + 6z}{6x + 6y} = \frac{z}{x}[/tex]

Factor out 2

[tex]\frac{4y + 3z}{3x + 3y} = \frac{z}{x}[/tex]

Cross multiply

[tex]4xy+3xz = 3xz + 3yz[/tex]

Cancel out the common terms

[tex]4xy = 3yz[/tex]

Divide both sides by y

[tex]4x = 3z[/tex]

Make z the subject

[tex]z =\frac{4}{3}x\\[/tex]

So, we have:

[tex]y = x[/tex] and [tex]z =\frac{4}{3}x\\[/tex]

Recall that:

[tex]xyz =480[/tex]

Substitute [tex]y = x[/tex] and [tex]z =\frac{4}{3}x\\[/tex]

[tex]x \times x \times \frac 43x = 480[/tex]

So, we have:

[tex]\frac 43x^3 = 480[/tex]

Multiply both sides by 3/4

[tex]x^3 = 360[/tex]

Take the cube roots of both sides

[tex]x = \sqrt[3]{360}[/tex]

Recall that:

[tex]y = x[/tex]

So, we have:

[tex]y = \sqrt[3]{360}[/tex]

Also, we have:

[tex]z =\frac{4}{3}x\\[/tex]

So, we have:

[tex]z =\frac{4}{3} \sqrt[3]{360}[/tex]

Hence, the dimension of the container of this size that has the minimum cost is [tex]x = \sqrt[3]{360}[/tex], [tex]y = \sqrt[3]{360}[/tex] and [tex]z =\frac{4}{3} \sqrt[3]{360}[/tex]

Read more about Lagrange multipliers at:

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Answer:

y = 14x

Step-by-step explanation:

First Way of Finding the Equation:

We can find the equation for this proportional relationship by subtracting two of the y-values from each other and then dividing that by the difference of two of the x-values. For now, I'll use the points (2, 28) and (1, 14).

[tex]\frac{28-14}{2-1} =\frac{14}{1} =14[/tex]

So, this proportional relationship has an equation of y = 14x.

Second Way of Finding the Equation:

Another way of finding the equation is to simply examine the table given. What are all the x-values multiplied by to get to their corresponding y-values? Well, one easy way of answering this question is looking at the point (1, 14) - 1 × 14 = 14, so the constant of proportionality must be 14.

From this information, we know that the equation must be y = 14x.

Hopefully that's helpful! :)

Answer: 1.8 x 103 meters

Step-by-step explanation:

The average of the two extremes is 1,700 meters.  This would be 1.7x10^3 in scientific notation.  None of the four options include this number.  But three stand out as total losers.  We can convert the answer options to see the difference:

O 1.7 x 102 meters  =    170 meters      [Loser]

O 1.8 x 103 meters  =  1800 meters

O 1.7 x 10-3 meters =  0.0017 meters   [Loser]

O 1.8 x 10-2 meters =  0.018 meters     [Loser]

Answer: How to calculate commission. This is a very basic calculation revolving around percents. Just take sale price, multiply it by the commission ...

Step-by-step explanation:

Answer:

A: Opposite

B: Same

Step-by-step explanation:

I'm not really sure, please tell me if I'm incorrect

Answer:

1,900 square feet; f(3) represents the total number of square feet the construction crew has paved after 3 hours.

The function of the construction crew is an illustration of a linear function

The value of f(3) is 1900, and f(3) represents the total number of square feet paved after working for 3 hours

The function is given as:

To calculate f(3), we substitute 3 for x

Multiply 300 and 3

Add 900 and 1000

This means that the value of f(3) is 1900.

And it represents the total number of square feet paved after working for 3 hours

1,900 square feet; f(3) represents the total number of square feet the construction crew has paved after 3 hours.

Answer:

is there a photo of a scatter plot?

Step-by-step explanation:

Answer:

Step-by-step explanation:

the sum of the interior angles of a triangle is 180°

180 - 70 = 110

110 = 12x + 2 + 15x

108 = 27x

108 : 27 = 4°

4 * 15 = 60° is your answer

check

15 * 4 + 12 * 4 + 2 + 70 = 180

60 + 48 + 72 = 180

the answer is good

Answer:

x=186.68

y=140

z=233.34

Step-by-step explanation:

easy method to solve since you have the answers to pick from

first triangle. we have two sides 175 and 105 and we know that 175 have to be the largest number, its the hypotenuse. which means

y=140,

cannot be 233 or 186 because both greater than 175

now next triangle. x-y-z, we already know "y" and "z" needs to be the largest number so it has to be

z= 233.34 and finally

x=186. 67

Answer:

x = 14[tex]\sqrt{2}[/tex]

Step-by-step explanation:

Since the triangle is 45- 45- 90 then it is isosceles with the 2 legs being congruent, both 14

Using Pythagoras' identity in the right triangle

x² = 14² + 14² = 196 + 196 = 392 ( take square root of both sides )

x = [tex]\sqrt{392}[/tex] = [tex]\sqrt{196(2)}[/tex] = [tex]\sqrt{196}[/tex] × [tex]\sqrt{2}[/tex] = 14[tex]\sqrt{2}[/tex]

Answer:

Acute angle

Step-by-step explanation:

Angles smaller than 90 degrees are acute

hope it helps :)

Answer:

People who bought tickets = 100%

                                             = 8000

People who bought their tickets in person = (100%-60%-15%) × 8000

                                                                       = 2000

The number of tickets sold online is 4800, by phone is 1200, and in person is 2000.

The Percentage is defined as representing any number with respect to 100. It is denoted by the sign %. The percentage stands for "out of 100." Imagine any measurement or object being divided into 100 equal bits.

Given that there were 8000 people at the festival. people bought their tickets online, by phone, or in person. based on a random sample of people at the festival, 60% bought their tickets online, and 15% bought their tickets by phone.

The number of the tickets will be calculated as below:-

Total tickets = 8000

Online tickets = 60% of 8000 = 8000 x 0.6 = 4800

By phone = 15% of 8000 = 8000 x 0.15 = 1200

In-person = 25% x 8000 = 0.25 x 89000 = 2000

Therefore, the number of tickets sold online is 4800, by phone is 1200, and in person is 2000.

To know more about percentages follow

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Answer:

Johnathan started out with 17 videogames

25-8=17

<ABD and <EBC are equal  to each other. In order to solve for the x value, set the equations  equal to each other;

4x = 2x + 40,

x = 20

Based off what angle you are trying to find, you would plug x = 20 into the equation.

Answer:

x = 48

Step-by-step explanation:

Given a secant and a tangent from an external point to the circle, then

the product of the external part and the entire secant is equal to the square of the measure of the tangent , that is

2(2 + x) = 10² = 100 ( divide both sides by 2 )

2 + x = 50 ( subtract 2 from both sides )

x = 48

Step-by-step explanation:

18.

the last one.

-4.9t² + 24.5t + 117.6 = 0

the ball starts at 117.6 meters height. then, during the first seconds the thrust upwards is adding height, until finally, with more and more seconds passing, gravity will win with a vengeance and pulls the ball down faster and faster than any other force in any other direction.

19.

the general solution for a quadratic equation

y = ax² + bx + c

is

x = (-b ± sqrt(b² - 4ac))/(2a)

in our case

x = t

a = -4.9

b = 24.5

c = 117.6

t = (-24.5 ± sqrt(600.25 - -4×4.9×117.6))/-9.8 =

= (-24.5 ± sqrt(600.25 + 2304.96))/-9.8 =

= (-24.5 ± sqrt(2905.21))/-9.8 = (-24.5 ± 53.9)/-9.8

t1 = (-24.5 + 53.9)/-9.8 = -3

t2 = (-24.5 - 53.9)/-9.8 = 8

a negative time does not make any sense, so the real solution is : the ball reached the ground after 8 seconds.

20.

now the equation is

-4.9t² + 24.5t + 117.6 = 49

but this is quickly transformed again into a "= 0" equation :

-4.9t² + 24.5t + 68.6 = 0

t = (-24.5 ± sqrt(600.25 - -4×4.9×68.6))/-9.8 =

= (-24.5 ± sqrt(600.25 + 1344.56))/-9.8 =

= (-24.5 ± sqrt(1944.81))/-9.8 = (-24.5 ± 44.1)/-9.8

t1 = (-24.5 + 44.1)/-9.8 = -2

t2 = (-24.5 - 44.1)/-9.8 = 7

again, negative time does not make sense.

the ball will be at 49 m height after 7 seconds.

Answer:

Because of the definition of congruent

Step-by-step explanation:

This problem may sound tricky, but it's not actually that hard. We now congruent means two things are the same, so for this problem, think of it as an equal sign. (Congruent doesn't mean equal, as an equal sign denotes the relationship that two things are the same if we know the concrete value of it.) So if AB=CD, CD=AB as you can swap two sides of an equation around and get the same answer. It's like saying 2=x ∴ x=2 (The dots mean therefore in math.)

Please consider a brainliest! Thank you!

Answer:

80%

Step-by-step explanation:

20:25*100 =

(20*100):25 =

2000:25 = 80

Now we have: 20 is what percent of 25 = 80

Question: 20 is what percent of 25?

Percentage solution with steps:

Step 1: We make the assumption that 25 is 100% since it is our output value.

Step 2: We next represent the value we seek with $x$.

Step 3: From step 1, it follows that $100\%=25$.

Step 4: In the same vein, $x\%=20$.

Step 5: This gives us a pair of simple equations:

$100\%=25(1)$.

$x\%=20(2)$.

Step 6: By simply dividing equation 1 by equation 2 and taking note of the fact that both the LHS

(left hand side) of both equations have the same unit (%); we have

$\frac{100\%}{x\%}=\frac{25}{20}$

Step 7: Taking the inverse (or reciprocal) of both sides yields

$\frac{x\%}{100\%}=\frac{20}{25}$

$\Rightarrow x=80\%$

Therefore, $20$ is $80\%$ of $25$.

Hopes This Helps :)

Answer: If it was the other way around I would have helped you  

Step-by-step explanation:

e.g.    

2q

Answer:

solution given:

[tex]log_{10} n=q[/tex]

now

[tex]  Log_{10 }n^2=?[/tex]

by using property of logarithms

[tex]log_{a} n^p=p log_{a}n [/tex]

now

[tex]  Log_{10 }n^2=2 Log_{10 }n[/tex]

=2q

since [tex]log_{10} n=q[/tex]

Step-by-step explanation:

Answer: 4

Step-by-step explanation:

 Slope = -2.000/2.000 = -1.000

 x-intercept = 0/1 = 0.00000

 f-intercept = 0/1 = 0.00000

x = 0

Answer:

Congress. would equal 80 due to x being worth 1/4 of y's total.

21 Line is mapped onto line m by a dilation centered at the origin with a scale factor of 2. The equation of line is 3x − y = 4. Determine and state an.

Answer:

111 minutes and 40 sec

Step-by-step explanation:

11x10=110 minutes

10 sec x 10 = 100 seconds = 1 minute 40 sec

110 minutes+1 minute+40 seconds= 111 minutes and 40 seconds

Answer: what number line

Step-by-step explanation:

Answer:

55.38 min

Step-by-step explanation:

A car travels,

182 km ⇒ 4 hours

And we have to find the time that it takes to travel 42 km .

Lets make a equation.

Let the unknown time be x

182 km ⇒ 4 hours

42 km ⇒ x

To make easy let's km in to meters and hours in to minutes

182000 m ⇒ 240 min

42000m ⇒ x

Now use cross multiplication.

[tex]182000x=240*42000\\[/tex]

[tex]182000x=10080000[/tex]

[tex]\frac{182000x}{182000} =\frac{1008000}{182000}[/tex]

[tex]x =55.38min[/tex]

Hope this helps you.

Let me know if you have any other questions :-)

Using the surface area of a rectangular prism, it is found that she will need 366 square inches of wrapping paper to wrap the box.

He wraps the box with paper outside, hence, the amount needed is the surface area.

The surface area of a rectangular prism of length l, width w and height h is given by:

[tex]S = 2(lw + lh + wh)[/tex]

In this problem, the dimensions of 11 inches long, 8 inches wide, and 5 inches tall mean that [tex]l = 11, w = 8, h = 5[/tex]. Hence:

[tex]S = 2[11(8) + 11(5) + 8(5)] = 366[/tex]

She will need 366 square inches of wrapping paper to wrap the box.

You can learn more about the surface area of a rectangular prism at https://brainly.com/question/1310421

Answer: the first graph (A)

Step-by-step explanation: are you actually low IQ or intellect this is the most easiest question I have ever seen I just finished this topic in my honor math class like last month in a week. BTW I am in the 9th grade

Now I got to tutor you so here you can use the process of elimination which you can see that < without the line below it means that the line is dotted and is the only one with a y-intercept of +2 is A and D are the only ligament answer now you dumc as i can't curse due to that i will get reported, so anyways go up 2 and go 1 to the right because it is 2x which is 2/1x rise/run and it is positive which means D is wrong because it has a negative slope which the only answer for this is A now get your (can't say) together and study.