a research methods professor creates a computer tutor to help students understand confounding and obscuring variables. before the second exam in the class, volunteers are randomly assigned to either interact with the computer tutor on the materials or to play angry birds on the computer for an equivalent time (30 minutes). although the students in the tutor group do significantly better on the exam the following day, many of the practice questions from the tutor are exactly the same as those on the exam. what is the main threat to concluding that the tutor was effective?

The critical value needed to test for independence between the type of restoration and sensory disorders is 6. 635.

To evaluate the correlation between sensory impairments and restoration type, a chi-square test of independence can be used. To determine the critical value for this statistical test, consult the chi-square distribution table at a 0.01 significance level.

The degrees of freedom for a chi-square test of independence :

Degrees of Freedom ( df ) = ( Number of Rows - 1 ) x ( Number of Columns - 1 )

The number of rows from the table = 2

Number of columns is also = 2

The df is therefore:

df = (2 - 1) x (2 - 1) = 1 x 1 = 1

The critical value for χ² with 1 degree of freedom at a 0. 01 significance level can be founding using the Chi - Square table to be approximately 6.635.

Find out more on critical value at https://brainly.com/question/14040224

#SPJ4

Full question is:

In recent years, concerns have been expressed about adverse health effects from amalgam dental restorations, which contain mercury. The table shows results from a study in which some patients were treated with amalgam restorations and others were treated with composite restorations that do not contain mercury. Use a 0. 01 significance level to find the critical value needed to test for independence between the type of restoration and sensory disorders.

Sylvia can fit 9 large cubic boxes and 240 small rectangular boxes into her car trunk.

We first need to convert all measurements to the same unit. Since the large cubic boxes are given in inches, we need to convert the dimensions of the trunk to inches as well.

The trunk measures 51 inches wide (4.25 ft x 12 in/ft), 48 inches deep (4 ft x 12 in/ft), and 53.33 inches high (4*1/3 ft x 12 in/ft).

Next, we need to determine how many large boxes can fit in the trunk. Since each large box is 16 inches wide,

we can fit 3 boxes across the width of the trunk:

(51 inches ÷ 16 inches = 3.19)

Similarly, we can fit 3 boxes deep and 3 boxes high.

Therefore, the maximum number of large boxes Sylvia can fit in her trunk is:

27 (3 x 3 x 3 = 27)

After fitting as many large boxes as possible, we can calculate the remaining volume of the trunk and use this to determine how many small boxes can fit.

The remaining volume is approximately 59,712 cubic inches (51 in x 48 in x 20 in).

Dividing this by the volume of each small box:

(3 in x 6 in x 4 in = 72 cubic inches)

We can fit 829 small boxes in the remaining space.

Therefore, Sylvia can fit a total of 27 large boxes and 829 small boxes in her trunk.

Learn more about measurements

brainly.com/question/2107310

#SPJ11

The size of the student body is approximately 1440 students.

To determine the size of the student body, we'll use the given information that 936 students represent 65% of the total number of students. We can set up a proportion to solve for the unknown total (let's call it "x"):

(65% of x) = 936

To express the percentage as a decimal, divide 65 by 100, which equals 0.65:

0.65 * x = 936

Next, to find the value of x, divide both sides of the equation by 0.65:

x = 936 / 0.65

x ≈ 1440

So, the size of the student body is approximately 1440 students. In this problem, we used the concept of percentage to find out the total number of students in the student body, knowing that 936 students (65%) attended the football game.

Learn more about percentage here: https://brainly.com/question/24339661

#SPJ11

The critical point (180, 120) will yield a maximum revenue of 23,700. So, the correct answer is the (180, 120).

To determine which critical point will yield a maximum revenue, we need to evaluate the objective function at each point and compare the results.

Objective Function: Revenue = 75x + 85y

1. Point (0,0):
Revenue = 75(0) + 85(0) = 0

2. Point (180, 120):
Revenue = 75(180) + 85(120) = 13500 + 10200 = 23700

3. Point (300,0):
Revenue = 75(300) + 85(0) = 22500 + 0 = 22500

Comparing the revenues at each point:
(0,0) - Revenue = 0
(180, 120) - Revenue = 23700
(300,0) - Revenue = 22500

The critical point (180, 120) will yield a maximum revenue of 23,700. So, the correct answer is the (180, 120).

Learn more about critical point,

https://brainly.com/question/30459381

#SPJ11

Answer:

Step-by-step explanation:

The value of x is 19 if the lines l and m are parallel.

The lines l and m are parallel

The corresponding angles are equal

We have to find the value of x

6x-9 = 5x+10

Let us take all the variable terms on one side

6x-5x=10+9

x=19

Hence, the value of x is 19 if the lines l and m are parallel.

To learn more on Coordinate Geometry click:

brainly.com/question/27326241

#SPJ1

To approximate the change in z = f(x, y) as x changes from −1 to −0.93 and y changes from 2 to 1.94, we can use the differential dz.

First, we need to find the partial derivatives of f with respect to x and y:

∂f/∂x = -10/x³(y²)
∂f/∂y = -10(x²)/y³

Then, we can use the following formula:

dz ≈ ∂f/∂x * Δx + ∂f/∂y * Δy

where Δx and Δy are the changes in x and y, respectively.

Substituting in the given values, we have:

Δx = -0.93 - (-1) = 0.07
Δy = 1.94 - 2 = -0.06

Using the partial derivatives we calculated earlier, we get:

dz ≈ (-10/-1.037³(2²)) * 0.07 + (-10((-1)²)/1.94³) * (-0.06)
dz ≈ -0.031

Therefore, the approximate change observed in z as x changes from −1 to −0.93 and y changes from 2 to 1.94 is -0.031.
To approximate the change in z using the differential dz, we first need to find the partial derivatives of z with respect to x and y. Given z = f(x, y) = 5/(x² + y²):

∂z/∂x = -10x/(x² + y²)²
∂z/∂y = -10y/(x² + y²)²

Now, we need to find the differential dz:

dz = (∂z/∂x)dx + (∂z/∂y)dy

Since x changes from -1 to -0.93, dx = -0.93 - (-1) = 0.07. Similarly, y changes from 2 to 1.94, so dy = 1.94 - 2 = -0.06.

Now, plug in the initial values of x and y (-1, 2):

∂z/∂x = -10(-1)/((-1)² + 2²)² = -10/25
∂z/∂y = -10(2)/((-1)² + 2²)² = -40/25

Now, plug in dx and dy into the dz equation:

dz = (-10/25)(0.07) + (-40/25)(-0.06) = 0.28 - 0.096 = 0.184

So, the approximate change in z when x changes from -1 to -0.93 and y changes from 2 to 1.94 is 0.184.

Visit here to learn more about differential brainly.com/question/31239084

#SPJ11

The coordinates of the resulting point, R′ are R' = (-9, -2)

From the question, we have the following parameters that can be used in our computation:

The point R(-2, 9) is rotated 90° clockwise around the origin.

This means thar

R = (-2, 9)

Rotation rule = 90° clockwise around the origin.

The rotation rule of 90° clockwise around the origin is

(x,y) becomes (y,-x)

So, we have

R' = (y, -x)

Substitute the known values in the above equation, so, we have the following representation

R' = (-9, -2)

Hence, the coordinates of the resulting point, R′ are R' = (-9, -2)

Read more about transformation at

https://brainly.com/question/27224272

#SPJ1

The graphs of the sinusoidal function for the question 1 to 4 created with MS Excel are attached

5. The function is; y = cos(θ) + 2

6. The function is; y = sin(2·θ) - 4

A sinusoidal function is a smooth periodic or repetitive function based on the sine or cosine of an angle.

The equations for the graphs in the sinusoidal function indicates that we get;

The period = 2·π/B

The horizontal shift = -C/B

The vertical shift = D

Where;

B = The coefficient of the angle, θ

C = The constant within the parenthesis

D = The constant term outside the sine or cosine function parenthesis

1. y = 2·sin(2·θ + 1)

The function indicates that the amplitude is 2, the period is 2·π/2 = π, the vertical shift is 0, and the horizontal shift is -1/2

Please find attached the graph of the function, created with MS Excel

2. y = -cos(θ) - 2

The amplitude is 1

The period is 2·π

The horizontal shift is 0

The vertical shift is -2

Please find attached the graph of the function y = -cos(θ) - 2, created with ms Excel

3. y = 4·cos(3·θ -2)

The amplitude is 4

The period is 2·π/3

The horizontal shift is 0

The vertical shift is -2

Please find attached the graph of the function y = 4·cos(3·θ -2), created with MS Excel

4. y = 3·sin(6·θ) - 1

The amplitude is 3

The period is π/3

The horizontal shift is 0

The vertical shift is -1

Please find attached the graph of the function y = 3·sin(6·θ) - 1, created with MS Excel

5. The points on the graph are;

Peak; (0, 3)

The next adjacent trough; (180, 1)

The adjacent peak; (360, 3)

Therefore;

The amplitude is 1

The period is 360°

The horizontal shift is 2

The vertical shift is 0

The peak point at θ = 0, indicates;

The function is; y = cos(θ) + 2

6. The points on the graph are;

Peak; (45, -3)

The next adjacent trough; (135, -5)

The adjacent peak; (225, -3)

Therefore;

The amplitude is 1

The period is 180 = π radians

The horizontal shift is 0

The vertical shift is -4

The function is; y = sin(2·θ) - 4

Learn more on sinusoidal functions here: https://brainly.com/question/2410297

#SPJ1

Answer is:

For the south region, the proportion of sales from current stores is approximately 58 %.

because this proportion is relatively close to the sales director's statistical model, the data is consistent with the model.

The given information states that the proportion of sales from current stores in the South region is approximately 58%. This value falls within the range of the sales director's statistical model, which could be an estimated value or a range of values based on past data or other sources. Since the proportion of sales falls within the expected range, the data is consistent with the model. This means that the actual value observed is not significantly different from the expected value, and there is no evidence to suggest that the model needs to be revised or updated.

Therefore, the answer to the second drop-down menu is "consistent". If the actual proportion of sales from current stores in the South region was significantly different from the expected value in the sales director's statistical model, then the answer would be "inconsistent". However, since the observed proportion is relatively close to the expected value, the data is consistent with the model.

To know more about statistical models:

https://brainly.com/question/30152102

#SPJ11

The difference between the median number of turkey sandwiches sold and the median number of ham sandwiches sold is 3.

First, let's find the median number of turkey and ham sandwiches sold.
To find the median:
1. Arrange the data in ascending order.
2. If there's an odd number of data points, the median is the middle value. If there's an even number of data points, the median is the average of the two middle values.

Turkey sandwiches sold: 7, 8, 12, 13, 15
Ham sandwiches sold: 6, 8, 9, 11, 16
Now let's find the medians:

Turkey median: There are 5 data points, which is odd, so the median is the middle value, 12.
Ham median: There are 5 data points, which is odd, so the median is the middle value, 9.
Finally, let's find the difference between the medians:
Difference = Turkey median - Ham median
Difference = 12 - 9
Difference = 3
You can read more about median at https://brainly.com/question/26177250

#SPJ11

The standard deviation for the data must be approximately $111.93.

Since we are given a range of values that encompasses about 95% of the data, we can assume that this range is within two standard deviations of the mean.

Thus, we can set up the following equation:

2σ = $444.47 - $220.61

Simplifying this equation, we get:

2σ = $223.86

σ = $111.93

Learn more about deviation on

https://brainly.com/question/24298037

#SPJ1

The equation that represents the total number of miles, m, Victoria should expect to be able to drive if she uses g gallons of gasoline is m = (19g).

We can determine the proportionality constant by dividing the total number of miles driven (76) by the number of gallons of gasoline burned (4), which gives us 19 miles per gallon (76/4 = 19).

We can then use this proportionality constant to create the equation m = (19g), where m represents the total number of miles Victoria should expect to be able to drive if she uses g gallons of gasoline. This equation tells us that for every additional gallon of gasoline burned, Victoria should expect to be able to drive an additional 19 miles.

For example, if Victoria were to burn 6 gallons of gasoline, she should expect to be able to drive 114 miles (6 x 19 = 114). This equation assumes that Victoria's car has a constant fuel efficiency of 19 miles per gallon.

For more questions like Equation click the link below:

https://brainly.com/question/29657983

#SPJ11

The area and cost of each of the lots is given below

The area and cost of each of the lots is calculated below

To calculate the rectangle trapezoid, it will be:

B = 140m

h = 50m

b = 70m

Note that Area of Lot 1 : A =(B+b)h/2

Hence Height will be:

A= (140m+ 70m) 50m/2

A = 5250 m²

Cost: C = 5250m² *800 pesos = $4,200,000

Lot 2 is another rectangle trapezoid:

B = 150m

b = 80m

h = 50m

Area: A= (150m+ 80m)50m/2

A = 5750 m²

Cost: C = 5750m²  x 800 pesos = $4,600,000

So, for Lot 3 which is a rectangle:

b = 70m

to = 50m

Area: A =a x b

W=50m x 70m

A  = 3500 m²

Cost: C = 3500m² x 800 pesos = $2,800,000

Lot 4 is a right triangle:

b = 70m

h = 50m

Area: A =b x h/2

A= (50m x 70m)/2

A = 1750 m²

Cost: C = 1750 m² x 800 pesos = $1,400,000

So for Lot 5 that is a rhomboid:

b = 150 base meters

h=50m

Area: A=b x h

A= (150m  x  50m

H = 7500 m²

Cost: C = 7500m² x  800 pesos = $6,000,000

So, for Lot 6 that is an isosceles triangle:

b = 140m

h= 50m

Area: A =b x h/2

A= (140m x  50m)/2

A = 3500 m²

Lastly, the Cost: C = 3500m²  x 800 pesos = $2,800,000

Learn more about area from

https://brainly.com/question/2607596

#SPJ4

See transcribed text below

The family of one of your colleagues, who had a piece of land with 7 adjoining lots, and they found themselves in need of selling them. They established a price per square meter of 800 pesos and they have to calculate the cost, based on the square meters that each lot has. Before continuing, review the terrain sketch and answer the questions

What is the area and cost of each of the lots?

This is a statistical question because it involves collecting data. Most employees work around 40 hours each week.

a. This is a statistical question because it involves collecting data on the number of hours worked by employees each week and analyzing the distribution or pattern of the data.

b. Here's a dot plot of the data provided:

   37: •
   38: ••
   39: ••
   40: ••••••••
   41: •••
   42: ••
   43: •
   47: •

The distribution of the data in the dot plot shows that the majority of employees worked around 40 hours each week, as this is where the data is most heavily clustered. Most of the data are clustered around 40 hours, with a peak at 40 hours. There is a gap between 43 and 47 hours.

c. Based on the distribution of the data, most employees work about 40 hours each week.

More on statistics: https://brainly.com/question/13312813

#SPJ11

The type of variable being studied in this case is a categorical variable, specifically a nominal variable.

Categorical variables are variables that can be classified or grouped. The categories in this example are the various modes of transportation utilized by off-campus students (drive alone, carpool, public transportation, walk, or a paid driving service).

Nominal variables are categorical variables with no intrinsic order or numerical value. Because the various modes of transportation in this study have no numerical value or inherent order, they are classified as nominal variables.

Learn more about variables at https://brainly.com/question/82796

#SPJ1

Each car on Mabel's train is a little less than half a foot long i.e., 3/8 feet long, or 0.375 feet long. This is solved by using simple mathematical operations.

To find the length of each car on Mabel's train, we can use the formula:

Total length of train = length of one car × number of cars

We are given that Mabel's train has 8 cars and is 3 feet long, so we can substitute those values into the formula and solve for the length of one car:

3 = x × 8

where x is the length of one car.

To solve for x, we can divide both sides by 8:

3/8 = x

Therefore, each car on Mabel's train is 3/8 feet long, or 0.375 feet long.

In other words, each car is a little less than half a foot long.

To help visualize this, imagine dividing the 3-foot length of the train into 8 equal parts. Each part would be 3/8 feet long, which is the length of one car. So when Mabel puts all 8 cars together, they form a train that is 3 feet long.

To know more about mathematical operations, refer to the link below:

https://brainly.com/question/29708824#

#SPJ11

Step-by-step explanation:

if this factorisation because I think you alr simplified, but here's the answer for factorisation anyways.

you can text me below in the comments section if that's not you want, I will try to answer if I can!!!

Answer:

3y(y - 2)(y - 1)

Step-by-step explanation:

Simplify by factoring

3y(y² - 3y + 2)

= 3y(y - 2)(y - 1)

The total cost to buy t movie tickets for $8.50 each is o only one, the number of ounces of tomato juice, j, in 2 quarts o only one, the number of pizzas to order, p, if each person eats 2 slices more than one, the greatest number of $6 notebooks, n, ed can buy with $36 only one, and the area, a, of a wall with a length of 5 meters and a height of 3 meters o only one.

1. The total cost to buy t movie tickets for $8.50 each:
- Only one value for the variable

The cost to buy a specific number of movie tickets at a fixed price will have only one total cost value.

2. The number of ounces of tomato juice, j, in 2 quarts:
- Only one value for the variable

There are 32 ounces in a quart, so 2 quarts will always have 64 ounces.

3. The number of pizzas to order, p, if each person eats 2 slices:
- More than one value for the variable

The number of pizzas needed depends on the number of people attending, which can vary, leading to different values for p.

4. The greatest number of $6 notebooks, n, Ed can buy with $36:
- Only one value for the variable

Since each notebook costs $6, Ed can buy exactly 6 notebooks with $36 (36/6 = 6).

5. The area, a, of a wall with a length of 5 meters and a height of 3 meters:
- Only one value for the variable

The area of a rectangle is calculated by multiplying its length and height. In this case, the area will always be 15 square meters (5m x 3m = 15m²).

Know more about area here:

https://brainly.com/question/16151549

#SPJ11

As per the given information in the question, we can compute that the correct option is C) 11.

According to the question:

[tex]f(x)=x^{2} -6x-4[/tex]

[tex]g(x)=5x+3[/tex]

Therefore,

[tex](f+g)(x)= f(x)+g(x) \\

          =x^{2} -6x-4+5x+3 \\

          =x^2-x-1[/tex]

Now, to find (f+g)(-3):

substituting x=-3 in the above equation

we get,

[tex](f+g)(-3)= (-3)^2-(-3)-1 \\

                         = 9+3-1 \\

                         =11[/tex]

Hence  (f+g)(-3)=11

To know about questions on function:

brainly.com/question/16976467

#SPJ4

The function f(x) = x² + 12x - 3 has two distinct real roots and no rational or complex roots. The possible rational roots are ±1 and ±3, but they are not actual roots of the equation.

To find the number of complex zeros and possible rational zeros of the function f(x) = x² + 12x - 3 = 0, we can use the same methods as in the previous question.

According to the rational root theorem, any rational root of the polynomial must be of the form p/q, where p is a factor of the constant term (-3) and q is a factor of the leading coefficient (1). The possible rational roots are therefore ±1, ±3.

To determine if there are any complex roots, we can use the quadratic formula. The solutions to the equation f(x) = 0 are given by

x = (-b ± √(b² - 4ac)) / 2a

Plugging in the coefficients of the polynomial, we get

x = (-12 ± √(12² - 4(1)(-3))) / 2(1)

x = (-12 ± √(156)) / 2

x = -6 ± 3√(13)

Since the discriminant (b² - 4ac) is positive, the square root is real, and the roots are two distinct real numbers. Therefore, there are no complex roots.

The possible rational roots we found earlier, ±1 and ±3, are not actual roots of the equation, since plugging them into the equation does not give us zero. Therefore, there are no rational roots either.

In conclusion, the equation f(x) = x² + 12x - 3 = 0 has two distinct real roots and no complex or rational roots.

To know more about complex zeros:

https://brainly.com/question/29055469

#SPJ4

--The given question is incomplete, the complete question is given

" State the number of complex zeros and the possible rational zeros for the function f(x) = x² + 12x -3 = 0

show your work"--

The surface area of the triangular prism is 720in²

A prism is a solid shape that is bound on all its sides by plane faces.

The surface area of a prism is expressed as

SA = 2B +ph

where p is the perimeter of the base and h is the height of the prism.

Base area = 1/2 bh

= 1/2 × 24 × 5

= 12 × 5

= 60 in²

Perimeter of the base = 24 +13 +13

= 50 in²

the height of the prism = 12 in

therefore SA = 2 × 60+ 12 × 50

= 120 + 600

= 720 in²

Therefore the surface area of the prism is 720 in²

learn more about surface area of prism from

https://brainly.com/question/1297098

#SPJ1

In the given question, if y, p and q vary jointly and p is 14 when y and q are equal to 2 and  p and y are equal to 7, we get q is equal to 14 using the  joint variation formula.

To solve this problem, we need to use the formula for joint variation, which states that y, p, and q vary jointly if there exists a constant k such that ypk = kq.

In this case, we know that when y=2 and q=2, p=14. So we can set up the equation: 2*14*k = 2kq

Simplifying this, we get: 28k = 2kq
Dividing both sides by 2k, we get: 14 = q
So when p=7 and y=7, we can use the same equation: 7*14*k = 7kq

Simplifying this, we get: 98k = 7kq
Dividing both sides by 7k, we get: q = 14

Therefore, when p and y are equal to 7, q is equal to 14.

To know more about joint variation refer here:

https://brainly.com/question/29181669#

#SPJ11

Answer:

64

Step-by-step explanation:

Answer:

64...i think

Step-by-step explanation:

125 - 88=37

88-64=24

PLS MARK BRAINLIEST

Answer:

1.5 for both

Step-by-step explanation:

Taking each number and multiplying it by 1.5 will get you the dilated coordinates

Answer:

Shape 1 and Shape 3

Step-by-step explanation:

An obtuse angle is an angle that is greater than 90° but less than 180°.

We can see that the first shape has 2 angles that are greater than 90°, making this a correct choice.
The second shape has 4 boxes, meaning the angles are exactly 90°, making this incorrect.

The third shape has 6 angles that are greater than 90°, making this another correct choice.

The last shape has all 3 angles under 90°, making this also incorrect.

So, the 1st and 3rd shapes are correct.

Hope this helps! :)

The values of distance and orbital periods of planets Mercury is 0.39AU and 0.242yrs,Venus 0.72AU distance and 0.616yrs,Earth 1AU distance and 1yrs,Mars 1.52AUdistance and 1.88,Jupiter 5.2AUdistance and 1.88 ,Saturn N/Adistance and NA years as infromation is not provided,Uranus 19.18AUdistance and 84yrs,Neptune 30.06AUdistance and165yrs.

Based on the given information, here are some key facts about the planets in our solar system:

- Mercury is the closest planet to the Sun, with a distance from the Sun of 0.39 astronomical units (AU). It has an orbital period of 0.242 years.
- Venus is the second planet from the Sun, with a distance of 0.72 AU. Its orbital period is 0.616 years.
- Earth is the third planet from the Sun, with a distance of 1 AU. Its orbital period is 1 year.
- Mars is the fourth planet from the Sun, with a distance of 1.52 AU. Its orbital period is 1.88 years.
- Jupiter is the fifth planet from the Sun, with a distance of 5.2 AU. Its orbital period is 11.86 years.
- Saturn is the sixth planet from the Sun, with a distance of N/A AU. Its orbital period is N/A.
- Uranus is the seventh planet from the Sun, with a distance of 19.18 AU. Its orbital period is 84 years.
- Neptune is the eighth planet from the Sun, with a distance of 30.06 AU. Its orbital period is 165 years.

Therefore the the distance and orbital periods are in increasing arrangement mercury, venus, earth, mars, jupiter, saturn ,uranus, neptune distance from the sun.

learn more about orbital periods : https://brainly.ph/question/11770468

#SPJ11

The unit rate for chapters per hour is calculated as 16/21

In order to find the unit rate for the number of chapters Gregory reads in an hour, we must firstly divide the total amount of chapters read by the amount of hours devoted to the activity:

= 2/3 chapters ÷ 7/8 hours

= 2/3 chapters × 8/7 hours

= 16/21 chapters per hour

Consequently, the unit rate for chapters per hour is calculated as 16/21, which already exists in its most simplified form.

Learn more about unit rate at

https://brainly.com/question/19493296

#SPJ1