Suppose we want to assess the effect of a one-day SAT prep class at a 5% level of significance. Scores on the SAT writing exam can range from 200 to 800. A random sample of 50 students takes the SAT writing test before and after a prep class. We test the hypotheses: LaTeX: H_0 H 0 : LaTeX: \mu=0 μ = 0 LaTeX: H_a H a : LaTeX: \mu>0 μ > 0 where LaTeX: \mu μ is the mean of the difference in SAT writing scores (after minus before) for all students who take the SAT prep class. The sample mean is 5 with a standard deviation of 18. Since the sample size is large, we are able to conduct the T-Test. The T-test statistic is approximately 1.96 with a P-value of approximately 0.028. What can we conclude?

Answers

Answer 1

The SAT prep class has no influence on the mean difference in SAT writing scores, hence the null-hypothesis (H0) states that the mean difference is zero.

The alternative theory (Ha) states that the SAT prep course has a positive impact on the mean difference in SAT writing scores, resulting in a mean difference that is greater than zero.

The sample size of 50 is sufficient for us to do the hypothesis test using the t-distribution.

The estimated t-test statistic is 1.96, and at the 5% level of significance, it is significant only if it is in the rejection zone of the null hypothesis (1.677 is the crucial value for a one-tailed test with 49 degrees of freedom).

The calculated p-value of 0.028 is less than the threshold of 0.05, the null hypothesis is also rejected in favour of the alternative hypothesis.

To draw the conclusion that the SAT prep course has a favourable impact on the mean difference in SAT writing scores. Particularly, at the 5% level of significance, the sample-mean difference of 5 is statistically significantly greater than zero.

Therefore, it is reasonable.

To know More about null-hypothesis visit:

https://brainly.com/question/28920252

#SPJ4


Related Questions

two dice are rolled. what is the probability that the sum of the numbers rolled is either 3 or 7 ? express your answer as a fraction in lowest terms or a decimal rounded to the nearest millionth

Answers

To find the probability of rolling a sum of either 3 or 7, we need to find the number of ways we can get each sum and divide by the total number of possible outcomes. For a sum of 3, the only way to get this is by rolling a 1 and a 2. There are two ways to arrange this: 1-2 and 2-1.


Probability = (Number of desired outcomes) / (Total number of possible outcomes)
Probability = 8 / 36

We can simplify the fraction by dividing both numerator and denominator by their greatest common divisor, which is 4:

Probability = (8/4) / (36/4)
Probability = 2/9

So, the probability of rolling a sum of 3 or 7 with two dice is 2/9, or approximately 0.222222 as a decimal rounded to the nearest millionth.

Learn more about probability here : brainly.com/question/11234923

#SPJ11

the national highway association is studying the relationship between the number of bidders on a highway project and the winning (lowest) bid for the project. of particular interest is whether the number of bidders increases or decreases the amount of the winning bid. project number of bidders, x winning bid ($ millions), y project number of bidders, x winning bid ($ millions), y 1 9 5.1 9 6 10.3 2 9 8.0 10 6 8.0 3 3 9.7 11 4 8.8 4 10 7.8 12 7 9.4 5 5 7.7 13 7 8.6 6 10 5.5 14 7 8.1 7 7 8.3 15 6 7.8 8 11 5.5 click here for the excel data file a. create a scatter plot of the data. a-2. choose the right option. b-1. calculate the correlation coefficient. (round your answer to 4 decimal places.) b-2. what does it indicate about the relationship between number of bidders and the winning bid? c-1. complete a regression analysis of the relationship. c-2. report and interpret the coefficient of determination. (round your answer to 2 decimal places.) d. compute the regression equation that predicts the winning bid. (negative value should be indicated by a minus sign. round your answers to 4 decimal places.) e. is the slope of the regression line significantly different from zero? multiple choice yes no f. estimate the winning bid if there were seven bidders. (round your answer to 4 decimal places.) g. compute the 95% prediction interval for a winning bid if there are seven bidders.

Answers

a-1: The amount of the winning bid if there were seven bidders is $8.6875 million.

b-1. A correlation coefficient of -0.8906

b-2. A strong negative correlation between the number of bidders and the winning bid.

c-1  R² value of 0.7933

c-2 The approximately 79.33% of the variation in the winning bid can be explained by the number of bidders.

d: The regression equation that predicts the winning bid is 5.5327 million dollars

e. The alternative hypothesis is that the slope is not equal to zero.

f. The estimated winning bid for a project with seven bidders is $6.3138 million.

g. We can be 95% confident that the actual winning bid amount for a project with seven bidders will fall within the range of $3.4362 million to $9.1914 million.

a-1. To create a scatter plot of the data, we plot the number of bidders (x-axis) against the winning bid in millions of dollars (y-axis) for each project.

Using the data set provided, we can calculate the slope and intercept of the line as follows:

Slope (b) = Σ[(X - x)(Y - x)] / Σ(X - x)²

Intercept (a) = y - bx

where x and yȲ are the mean values of X and Y, respectively. Using the given data, we can calculate x = 6.6 and Y = 8.32.

Using these equations, we can calculate the slope and intercept of the line as:

b = -0.1744

a = 9.8983

Therefore, the equation of the line is:

Y = 9.8983 - 0.1744X

To estimate the winning bid if there were seven bidders, we can substitute X = 7 into the equation and solve for Y:

Y = 9.8983 - 0.1744(7)

Y = 8.6875

b-1. Using the given data, we get a correlation coefficient of -0.8906, rounded to four decimal places.

b-2. The correlation coefficient indicates the strength and direction of the linear relationship between the number of bidders and the winning bid. A value of -1 indicates a perfect negative correlation, while a value of +1 indicates a perfect positive correlation. A value of 0 indicates no correlation. In this case, the correlation coefficient of -0.8906 suggests a strong negative correlation between the number of bidders and the winning bid.

c-1. To complete a regression analysis of the relationship, we use the formula:

y = a + bx

where y is the dependent variable (winning bid), x is the independent variable (number of bidders), a is the y-intercept, and b is the slope of the regression line.

Using the given data and performing regression analysis, we get:

y = 10.14 - 0.6261x

c-2. Using the given data, we get an R² value of 0.7933, rounded to two decimal places. This means that approximately 79.33% of the variation in the winning bid can be explained by the number of bidders.

d. To compute the regression equation that predicts the winning bid, we use the equation obtained in part c-1:

y = 10.14 - 0.6261x

So, if there were, for example, 7 bidders, we can estimate the winning bid as:

y = 10.14 - 0.6261(7) = 5.5327 million dollars, rounded to 4 decimal places.

e. To test whether the slope of the regression line is significantly different from zero, we can perform a t-test on the slope coefficient (b). The null hypothesis is that the slope is equal to zero, and the alternative hypothesis is that the slope is not equal to zero.

f. The relationship between the number of bidders and the winning bid amounts for the collected data. The resulting regression equation for this data is:

y = 10.0643 - 0.4771x

To estimate the winning bid for a project with seven bidders, we can plug in the value of x = 7 into the regression equation:

y = 10.0643 - 0.4771(7)

y = 6.3138

g) For a 95% confidence interval and n = 15 - 2 = 13 degrees of freedom, the t-value is 2.160. Therefore, the 95% prediction interval for a winning bid with seven bidders is:

6.3138 ± 2.160 x 1.4587

= (3.4362, 9.1914)

To know more about equation here

https://brainly.com/question/10413253

#SPJ4

a 24 factorial design has been run in a pilot plant to investigate the effect of four factors on the molecular weight of a polymer. the data from this experiment are as follows (values are coded by dividing by 10). (a) construct a normal probability plot of the effects. which effects are active? (b) construct an appropriate model. fit this model and test for significant effects. (c) analyze the residuals from this model by constructing a normal probability plot of the residuals and plotting the residuals versus the predicted values of y.

Answers

A 24 factorial design has been run in a pilot plant to investigate the effect of four factors on the molecular weight of a polymer.


(a) To construct a normal probability plot of the effects, follow these steps:
1. Calculate the main effects (A, B, C, D) and interaction effects (AB, AC, AD, BC, BD, CD, ABC, ABD, ACD, BCD, ABCD) using the given data.
2. Rank the effects in ascending order based on their absolute values.
3. Calculate the percentile for each effect using the formula: (i - 0.5) / n, where i is the rank and n is the total number of effects (in this case, 15).
4. Find the corresponding z-scores for each percentile from a standard normal distribution table.
5. Plot the z-scores against the effects in a scatter plot.

Active effects are those that deviate significantly from the straight line formed by the majority of the points in the plot.

(b) To construct an appropriate model and test for significant effects:
1. Include only the active effects identified in step (a) in your model.
2. Fit the model using multiple linear regression or another suitable method.
3. Perform hypothesis testing on the coefficients of the effects included in the model using t-tests or F-tests. If the p-value is below a chosen significance level (e.g., 0.05), then the effect is considered significant.

(c) To analyze the residuals from the model:
1. Calculate the residuals (observed - predicted values) for each observation.
2. Create a normal probability plot of the residuals using the same method described in step (a).
3. If the residuals follow a straight line, it indicates that they are normally distributed, which is an important assumption in linear regression models.
4. Plot the residuals against the predicted values of Y in a scatter plot to check for any patterns or trends. If no patterns are observed, it suggests that the model is a good fit for the data.

By following these steps, you'll be able to identify the active effects, construct an appropriate model, and analyze the residuals.

to learn more about polymer click here:

brainly.com/question/29775574

#SPJ11

Write an expression that represents the net change in rupees bank account Val after paying for fuel at the gas station

Answers

The net change in her account after paying for fuel is represented by expression [tex]B - F[/tex] where B is balance of rupee and F is fuel purchase price.

What expression be represent the net change?

An expression refers to statement that have minimum of two numbers or variables and operator connecting them

Let us say Val's bank account has a balance of B rupees and she purchases fuel for F rupees. Then, the net change in her bank account after paying for fuel can be represented by the expression which is [tex]B - F[/tex].

Read more about expression

brainly.com/question/1859113

#SPJ1

In a random sample of 2,282 college students, 356 reported getting 8 or more hours of sleep per night. Create a 95% confidence interval for the proportion of college students who get 8 or more hours of sleep per night. Use Excel to create the confidence interval, rounding to four decimal places.

Answers

Answer: To create a 95% confidence interval for the proportion of college students who get 8 or more hours of sleep per night, we can use the following formula:

CI = p ± z*(sqrt((p*(1-p))/n))

where:

p = proportion of college students who get 8 or more hours of sleep per night (356/2282 = 0.1559)

n = sample size (2282)

z = z-score corresponding to the desired level of confidence (for a 95% confidence level, z = 1.96)

Substituting the given values, we get:

CI = 0.1559 ± 1.96*(sqrt((0.1559*(1-0.1559))/2282))

CI ≈ (0.1301, 0.1818)

Rounding to four decimal places, the 95% confidence interval for the proportion of college students who get 8 or more hours of sleep per night is (0.1301, 0.1818).

Answer:

 (0.1411, 0.1709)

Step-by-step explanation:

Please Please prioritize the last part

A mistake was made in mixing the lemonade for the concession stand, but you can fix it!
The lemonade comes in 100% juice concentrate, but you only serve it as 70% solution. Unfortunately, one batch got overwatered, so you have 4 quarts of 50% solution.

How much 100% concentrate do you need to add in order to get the 70% solution?
How much of the 70% solution will you have?

Set up a system of equations and then show each step to solve it.

Answers

The total is 6 and 2/3 quarts of 70%

How to solve

Given the data:

0.5(4)+1x=(x+4)0.7

2+x=0.7x+2.8

minus 0.7x both sides

2+0.3x=2.8

minus 2 from both sides

0.3x=0.8

divide both sides by 0.3

x=8/3

adds 8/3 quarts or 2 and 2/3 quarts

total is 4+ 2 and 2/3 or 6 and 2/3

adds 2 and 2/3 quarts of 100%

total is 6 and 2/3 quarts of 70%

Read more about percentage here:
https://brainly.com/question/24877689
#SPJ1

The volume of this cube is 125 cubic inches. What is the value of r?
(cube with 3 r's)

Answers

The value of "r" in this cube is 5 inches.

Now that we have an understanding of volume and the formula for the volume of a cube, we can use the given information to solve for the value of "r". We are given that the volume of the cube is 125 cubic inches, so we can set up the equation as follows:

V = r³

125 = r³

To solve for "r", we need to find the cube root of 125. We can do this by using a calculator or by recognizing that 125 is a perfect cube. The cube root of 125 is 5, so we can substitute this value back into the original equation to find the value of "r".

r³ = 125

r³ = 5³

r = 5

We can check our answer by calculating the volume of the cube using the value of "r" that we found:

V = r³

V = 5³

V = 125 cubic inches

Our calculated volume matches the given volume, confirming that our solution for the value of "r" is correct.

To know more about volume here

https://brainly.com/question/11168779

#SPJ4

Calcula la energía cinética de una

mosca cuya masa es m= 4g y su velocidad es de 5m/s

Answers

Answer:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

Step-by-step explanation:

Assume that a procedure yields a binomial distribution with n trials and the probability of success for one trial is p. Use the given values of n and p to find the mean mu μ and standard deviation sigma σ. ​Also, use the range rule of thumb to find the minimum usual value mu minus 2 sigma μ−2σ and the maximum usual value mu plus 2 sigma μ+2σ. n equals = 200​, p equals = 0.6

Answers

In summary: Mean (μ): 120, Standard deviation (σ): 6.93, Minimum usual value (μ - 2σ): 106.14 and Maximum usual value (μ + 2σ): 133.86

To find the mean mu μ of the binomial distribution, we use the formula mu = n*p. Therefore, mu = 200*0.6 = 120.

To find the standard deviation sigma σ, we use the formula sigma = sqrt(n*p*(1-p)). Therefore, sigma = sqrt(200*0.6*0.4) = 6.93.

Using the range rule of thumb, we can estimate the minimum usual value by subtracting 2 times the standard deviation from the mean, and the maximum usual value by adding 2 times the standard deviation to the mean. Therefore, the minimum usual value is mu - 2*sigma = 120 - 2*6.93 = 106.14, and the maximum usual value is mu + 2*sigma = 120 + 2*6.93 = 133.86.

So, in summary, the mean mu μ of the binomial distribution is 120, the standard deviation sigma σ is 6.93, the minimum usual value mu minus 2 sigma μ−2σ is 106.14, and the maximum usual value mu plus 2 sigma μ+2σ is 133.86.
For a binomial distribution, the mean (μ) and standard deviation (σ) can be calculated using the formulas:

μ = n * p
σ = √(n * p * (1 - p))

Given n = 200 and p = 0.6, we can find μ and σ:

μ = 200 * 0.6 = 120
σ = √(200 * 0.6 * (1 - 0.6)) = √(200 * 0.6 * 0.4) = √48 ≈ 6.93

Next, we can use the range rule of thumb to find the minimum and maximum usual values:

Minimum usual value (μ - 2σ):
120 - (2 * 6.93) = 120 - 13.86 ≈ 106.14

Maximum usual value (μ + 2σ):
120 + (2 * 6.93) = 120 + 13.86 ≈ 133.86

In summary:
Mean (μ): 120
Standard deviation (σ): 6.93
Minimum usual value (μ - 2σ): 106.14
Maximum usual value (μ + 2σ): 133.86

Visit here to learn more about binomial distribution brainly.com/question/31197941

#SPJ11

-5√243-3√27
√500+√20+11√5
2√45+2√90+3√45
3√54+3√3-2√384
3√7+2√32-4√175
√20+2√80+√72-√5
-3√28+8√3-√3007√112
4√24-2√80+11√6-3√216

Answers

Answer: -8969.31346074

Explanation:  its the answer because thats what i got when i did the math

The process of using data to forecast what will happen in the future is known as
-descriptive analytics
-predictive analytics
-prescriptive analytics
-operations research
-management science

Answers

The process of using data to forecast what will happen in the future is known as predictive analytics.

Predictive analytics involves analyzing historical data to identify patterns and trends that can be used to make predictions about future events or behaviors.

A variety of techniques, such as regression analysis, time series analysis, and machine learning algorithms.

Predictive analytics is an important tool for businesses and organizations that want to make data-driven decisions and stay ahead of the competition.

It can be used in a variety of applications, such as sales forecasting, demand planning, fraud detection, and risk management.

By using predictive analytics, organizations can identify potential risks and opportunities, optimize their operations, and improve their bottom line.

Predictive analytics is not a crystal ball that can predict the future with 100% accuracy.

The predictions made using predictive analytics are based on historical data, and there is always a degree of uncertainty and risk involved.

It is important to understand the limitations of predictive analytics and to use it in conjunction with other tools and methods, such as expert judgment and qualitative analysis.

Predictive analytics is the process of using data to forecast what will happen in the future.

It is a powerful tool for businesses and organizations that want to make data-driven decisions, but it should be used with caution and in conjunction with other methods.

For similar questions on data

https://brainly.com/question/24326172

#SPJ11

Alice and Bob the end the nice restaurant. At the end of the meal, Alice has eaten C_A dollars worth of food, and in her wallet a set of bills A = a_1, a_2 ..., a_n Similarly, Bob owes the restaurant c_B dollars and has bills B = {B_1, B_2, ....b_m}. Now, Alice and Bob are very calculating people, so they agree that each of them should pay their fair share (C_A and c_B, respectively). One thing they don't mind doing, however, is fairly trading bills. That is, Alice can exchange a subset A' subsetorequalto A of her bills for for a subset B' subsetorequalto B of Bob's bills, so long as sigma _a element A' a = sigma _b element B' b. Under the above EA' conditions, Alice and Bob wish to find, after trading as many times as desired, subsets of their bills A*, B* such that sigma _a element A* a = c_A and sigma _b element B* b = c_B. Show that FAIR DATE is NP-complete.

Answers

FAIR DATE is both in NP and NP-hard, we can conclude that FAIR DATE is NP-complete.

To prove that FAIR DATE is NP-complete, we need to show two things: (1) FAIR DATE is in NP, and (2) FAIR DATE is NP-hard.

1. FAIR DATE is in NP:
We can easily verify a potential solution for FAIR DATE in polynomial time. Given subsets A* and B*, we can check if the sum of the bills in A* equals c_A and the sum of the bills in B* equals c_B. This verification can be done in O(n) time for Alice's bills and O(m) time for Bob's bills, where n and m are the number of bills Alice and Bob have, respectively.

2. FAIR DATE is NP-hard:
To show that FAIR DATE is NP-hard, we need to reduce a known NP-complete problem to it. Let's choose the PARTITION problem for this reduction. In the PARTITION problem, given a set S of integers, we need to determine if there exists a subset S' of S such that the sum of the elements in S' is equal to half the sum of all elements in S.

Reduction: Given an instance of PARTITION, we can create an instance of FAIR DATE as follows:
- Let Alice's bill be the set A = S, and c_A = 1/2 * (sigma_a ∈ A, a).
- Let Bob's bill be the set B = {}, and c_B = 0.

Now, if there exists a subset A* of A such that sigma_a ∈ A* a = c_A, then this subset is the solution to the PARTITION problem as well. Conversely, if there is a solution to the PARTITION problem, then there exists a subset A* such that sigma_a ∈ A* a = c_A.

Since we can perform this reduction in polynomial time, FAIR DATE is NP-hard.


to learn more about  polynomial click here:

brainly.com/question/9195802

#SPJ11

PLEASE ASWER ASAP

Solve for b and c. Select BOTH correct answers.

Answers

The lengths b and c are given as follows:

[tex]b = 4\sqrt{3}[/tex]c = 8.

What are the trigonometric ratios?

The three trigonometric ratios are the sine, the cosine and the tangent, and they are defined as follows:

Sine of angle = length of opposite side to the angle divided by the length of the hypotenuse.Cosine of angle = length of adjacent side to the angle divided by the length of the hypotenuse.Tangent of angle = length of opposite side to the angle divided by the length of the adjacent side to the angle.

For the angle of 30º, we have that:

4 is the opposite side.b is the adjacent side.

Hence the length b is obtained as follows:

tan(30º) = 4/b

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

[tex]b = 4\sqrt{3}[/tex]

Applying the Pythagorean Theorem, the length c is given as follows:

[tex]c^2 = 4^2 + (4\sqrt{3})^2[/tex]

c² = 64

c = 8.

More can be learned about trigonometric ratios at brainly.com/question/24349828

#SPJ1

1. consider the following data: x1 x2 y 2 -2 -2 2 2 5 1 0 4 0 2 10 0 -2 8 (a) one wish to use the multiple linear regression model to analysis this data. please specify the theoretical linear model for this data and also specify the standard assumptions in the model. (b) u se sas to find the regression l ine f or the above model. (c) one wishes to test whether the model is overall useful. set up the null and alternative hypotheses. (d) what test statistic will be used for the above test? what conclusion can be made from the sas output? (e) compute r2 and adjusted r2.

Answers

Adjusted R² is a modified version of R² that accounts for the number of independent variables in the model, making it more suitable for comparing models with different numbers of independent variables.

(a) To analyze this data using the multiple linear regression model, the theoretical linear model can be written as:

y = β0 + β1 * x1 + β2 * x2 + ε

where y is the dependent variable, x1 and x2 are the independent variables, β0 is the intercept, β1 and β2 are the coefficients of x1 and x2, respectively, and ε is the error term.

The standard assumptions in this model are:
1. Linearity: The relationship between the dependent and independent variables is linear.
2. Independence: The observations are independent of each other.
3. Homoscedasticity: The variance of the error term is constant across all levels of the independent variables.
4. Normality: The error term is normally distributed.

(b) Unfortunately, I cannot run SAS to find the regression line for the above model. Please use the SAS software on your computer to perform this task.

(c) To test whether the model is overall useful, set up the null and alternative hypotheses as follows:

H0: β1 = β2 = 0 (The model is not useful; the independent variables x1 and x2 do not explain any variation in y)
Ha: At least one of β1 or β2 is not equal to 0 (The model is useful; at least one of the independent variables explains the variation in y)

(d) The test statistic used for the above test is the F-statistic, calculated as (explained variance / number of independent variables) / (unexplained variance / degrees of freedom of residuals). Check the SAS output for the F-statistic and its corresponding p-value to determine if you should reject or fail to reject the null hypothesis.

(e) The R² and adjusted R² values can also be found in the SAS output. R² represents the proportion of the total variation in y that is explained by the independent variables in the model.

Learn more about linear regression here:

brainly.com/question/29665935

#SPJ11

Find the measurement of 0 in radians rounded to 2 decimal places

Answers

The measurement of 0 in radians is 0.00

A radian is a unit of measurement for angles, defined as the ratio of the length of an arc of a circle to the radius of that circle. One radian is equal to the angle subtended at the center of a circle by an arc whose length is equal to the radius of the circle.

To find the measurement of 0 in radians, we can use the fact that 0 degrees is equal to 0 radians. This is because an angle of 0 degrees subtends an arc of length 0 on a circle of any radius, which means that the ratio of the arc length to the radius is also 0.

We can round this answer to two decimal places as 0.00 radians.

To know more about radians here

https://brainly.com/question/7721249

#SPJ4

find the rectangular equation for the surface by eliminating the parameters from the vector-valued function r(u,v)=ui+vj+v/2k

Answers

The rectangular equation for the surface is either y = 2kzj or z = y/2kj, depending on how you choose to eliminate the parameters.

To eliminate the parameters from the vector-valued function r(u,v)=ui+vj+v/2k and find the rectangular equation for the surface, we need to solve for u and v in terms of x, y, and z.

Starting with the x-coordinate:

ui = x
=> u = x/i

Moving on to the y-coordinate:

vj = y
=> v = y/j

Finally, for the z-coordinate:

v/2k = z
=> v = 2kz

Substituting the expressions for u and v in terms of x, y, and z, we get the rectangular equation:

x/i = u
y/j = v
2kz = v

Simplifying, we can write this as:

x/i = u
y/j = 2kz
y = 2kzj
or
x/i = u
z = v/2k
x/i = u
z = y/2kj

So the rectangular equation for the surface is either y = 2kzj or z = y/2kj, depending on how you choose to eliminate the parameters.

to learn more about equation click here:

brainly.com/question/152438

#SPJ11



mariana earned a score of 338 on exam a that had a mean of 350 and a standard deviation of 40. she is about to take exam b that has a mean of 650 and a standard deviation of 20. how well must mariana score on exam b in order to do equivalently well as she did on exam a? assume that scores on each exam are normally distributed.

Answers

In order to perform equivalently well on exam B as she did on exam A, Mariana needs to achieve a score that is at least equivalent to her Z-score on exam A. Using the Z-score formula, we can calculate that Mariana's Z-score on exam A was -0.3. To achieve an equivalent score on exam B, we need to calculate the raw score that corresponds to a Z-score of -0.3 on exam B. This can be done using the formula Z = (X - μ) / σ. Solving for X, we get X = Z * σ + μ. Plugging in the values for exam B, we get X = -0.3 * 20 + 650 = 643.

In order to compare the performance on two different exams with different means and standard deviations, we use Z-scores to standardize the data. This allows us to compare scores on different scales. The formula to calculate Z-score is Z = (X - μ) / σ, where X is the raw score, μ is the mean, and σ is the standard deviation. The Z-score tells us how many standard deviations a score is from the mean. A Z-score of 0 means the score is at the mean, while a positive Z-score indicates that the score is above the mean and a negative Z-score indicates that the score is below the mean.

Mariana needs to achieve a score of at least 643 on exam B to perform equivalently as she did on exam A.

To know more about Z-Score visit:

https://brainly.com/question/15016913

#SPJ11

Find the Confidence Interval Given a Population Proportion
Finding the Confidence Interval With a Proportion
IMPORTANT: When finding confidence intervals for proportions, they should only be used if the number of successes np′ and the number of failures nq′ are both greater than 5.

Answers

We can say with 95% confidence that the proportion of students in the school who prefer math is between 0.504 and 0.696.

What is Confidence Interval?

A confidence interval is a range of values that is likely to contain the true value of a population parameter, such as a mean or proportion.

To find a confidence interval for a population proportion, you can use the following formula:

CI = p ± z*(√(p*q/n))

Where:

CI represents the confidence interval

p is the sample proportion

q is the complement of the sample proportion (q = 1 - p)

n is the sample size

z is the z-score associated with the desired level of confidence

The z-score is determined based on the desired level of confidence and can be found in a standard normal distribution table or calculated using statistical software. For example, if you want a 95% confidence interval, the z-score would be 1.96.

It's important to note that this formula should only be used if the number of successes np' and the number of failures nq' are both greater than 5. If this condition is not met, the normal approximation may not be accurate and other methods should be used.

To use this formula, you would follow these steps:

Calculate the sample proportion (p) by dividing the number of successes by the sample size.

Calculate q by subtracting p from 1 (q = 1 - p).

Determine the z-score based on the desired level of confidence.

Calculate the confidence interval using the formula above.

For example, let's say you want to find a 95% confidence interval for the proportion of students in a school who prefer math over other subjects. You survey a random sample of 100 students and find that 60 prefer math.

Calculate the sample proportion: p = 60/100 = 0.6

Calculate q: q = 1 - 0.6 = 0.4

Determine the z-score for a 95% confidence interval: z = 1.96

Calculate the confidence interval: CI = 0.6 ± 1.96*(√(0.6*0.4/100)) = (0.504, 0.696)

Therefore, we can say with 95% confidence that the proportion of students in the school who prefer math is between 0.504 and 0.696.

To learn more about Confidence Interval visit:

https://brainly.com/question/15712887

#SPJ4

what is the answer to

9.578x3

Answers

Answer:

28.734

Step-by-step explanation:

Each week you collect 20 cards. Your friend collects 12 cards each week. How many cards does your friend have if you have 240 cards?

Answers

If you have 240 cards and collect 20 cards per week, you have 96 cards after 8 weeks and your freind have 240 cards in 7.5 weeks.

First, we need to find the total number of cards collected per week by both you and your friend

Total cards collected per week = your cards + friend's cards

Total cards collected per week = 20 + 12

Total cards collected per week = 32

Now, we can find the number of weeks it would take for your friend to collect 240 cards

240 cards ÷ 32 cards per week = 7.5 weeks

Since we cannot have a fractional number of cards, we need to round up to the nearest whole number of weeks. Therefore, it would take your friend 8 weeks to collect 240 cards.

To know more about collect cards:

https://brainly.com/question/19798532

#SPJ4

describe a hypothesis test study that would help your work or conclusions in some way. describe what variable would be tested and what would be your guess of the value of that variable. then include how the result, if the null were rejected or not, might change your conclusions or actions in some way.

Answers

If the null hypothesis is rejected, and the proportion of customers willing to pay more is significantly different from 10%, this would support my hypothesis that customers are willing to pay more for eco-friendly packaging.

Let's say you work for a company that has been using a certain type of packaging material for their products. However, there have been concerns raised about the environmental impact of this material, and the company is considering switching to a more eco-friendly option. You believe that customers would be willing to pay more for products that are packaged with the eco-friendly material, but you need to test this hypothesis.

Variable: The variable that would be tested is whether customers are willing to pay more for products that are packaged with the eco-friendly material.

Guess of value: I would guess that customers would be willing to pay more for eco-friendly packaging, but I'm not sure how much more. Let's say my guess is that customers would be willing to pay 10% more for products packaged with the eco-friendly material.

Hypothesis test: To test this hypothesis, I would conduct a survey where I randomly select a sample of customers and ask them if they would be willing to pay more for products packaged with the eco-friendly material. I would then compare the proportion of customers who are willing to pay more to my guess of the value (10%).

Null hypothesis: The null hypothesis would be that the proportion of customers willing to pay more for eco-friendly packaging is not significantly different from 10%.

Alternative hypothesis: The alternative hypothesis would be that the proportion of customers willing to pay more for eco-friendly packaging is significantly different from 10%.

 If the null hypothesis is not rejected, this would suggest that customers are not willing to pay more for eco-friendly packaging, and the company may need to reconsider their decision to switch to the more expensive material.

To learn more about proportion visit:

brainly.com/question/30657439

#SPJ11

some positive integers have exactly four positive factors. for example, 35 has only 1, 5, 7 and 35 as its factors. what is the sum of the smallest five positive integers that each have exactly four positive factors?

Answers

Answer:

The smallest five positive integers that each have exactly four factors are 6, 8, 10, 14, and 15.

6 + 8 + 10 + 14 + 15 = 53

What is an equation of the linear relationship in slope-intercept form?

y=?x-?

Answers

An equation of the linear relationship in slope-intercept form is y = 3x - 4.

How to determine an equation of this line?

In Mathematics and Geometry, the point-slope form of a straight line can be calculated by using the following mathematical expression:

y - y₁ = m(x - x₁)

Where:

x and y represent the data points.m represent the slope.

First of all, we would determine the slope of this line;

Slope (m) = (y₂ - y₁)/(x₂ - x₁)

Slope (m) = (2 + 4)/(2 - 0)

Slope (m) = 6/2

Slope (m) = 3.

At data point (0, -4) and a slope of 3, a linear equation for this line can be calculated by using the point-slope form as follows:

y - y₁ = m(x - x₁)

y + 4 = 3(x - 0)  

y = 3x - 4

Read more on point-slope here: brainly.com/question/24907633

#SPJ1

I need help with these questions

Volume & S.A. of a Cone

Answers

1. The surface areas of the cones are;

1)  56.52 in²  2) 565.20ft²  3) 235.50 yd² 4) 898.04ft²   5) 942.00yd²

6) 75.36 in²   7) 1306.24yd²   8) 405.04in²  9. 339.12 ft²

2. The volumes of the cones are;

1) 84.78 in³  2). 564.15ft³  3) 4710yd³  4) 2712.96in³  5) 20.93ft³  6) 870.82yd³  7)  7846.86in³

3.  The volume of the cone-shaped Santa hat is 75.36in³.

How do you calculate surface area and volume of a cone?

For the normal cones, we use the formula  πr² + πrl to calculate the surface area.

(3.14 x 25) + (3.14x10x5) =  235.50 yd²

(3.14 x 121) + (3.14x15x11) = 898.04ft²

However, for cones like the ones in 6 and 8, we use a slightly different formula. √H² + r² = L first and then  π x r x (r + L).

For example  6.  H= 4in r=3in

⇒ √(4^2 + 3^2) =5

⇒  3.14 x 3 x (3 + 5) =75.36

To calculate the volume, we use the formula (V) = (1/3) x π x r² x H

For example,  H= 9in   r=3in ⇒

(1/3) x 3.14 x 3² x 9 = 84.78in³

The answers provided are based on the information in the picture;

1. Find the surface area of each cone. Round your answer to two decimal places ( use π = 3.14)

1. L = 7in  r=2in   2. L=11ft  r=9ft   3. L=10yd r=5yd   4. L=15ft  r=11ft

5. L=20yd  r=10yd   6.  L= 4in r=3in   7. L=19yd  r= 13yd   8. H=14in  r= 8in

9. L=12ft  r=6ft

2. Find the volume of each cone. Round to 2 decimal places. ( use π = 3.14).

1. H= 9in   r=3in     2. H= 11ft   r= 7ft     3. H=20yd   r=15yd  4. H=18in  r= 12in 5. H=5ft  r=2ft    6. H=13yd  r=8yd  7. H= 17in  r= 21

3. For Christmas, Lily make paper cones santa hat. If the height and radius of the cone are 8 inches and 3 inches respectively, what is the volume of the hat? ( use π = 3.14)

Find more exercises on surface area of cones;

https://brainly.com/question/12648760

#SPJ1

find the velocity and position vectors of a particle that has the given acceleration and the given initial velocity and position.a(t) = 5i + 8j, v(0) = k, r(0) = iv(t) = _______r(t) = _______

Answers

Answer:

a(t) = 5i + 8j v(t0 = integration of a(t) v

Step-by-step explanation:

Which of the following is equivalent to
60 1/2

Answers

Answer: 121/2 = 242/4=363/6

Step-by-step explanation:

What was Newton’s term for a derivative?

Answers

Newton's term for a derivative was "fluxions."

In his mathematical works, particularly in his book "Philosophiæ Naturalis Principia Mathematica," Newton advanced the idea of fluxions as a means of calculating quotes of exchange and slopes of curves.

He used the notation of a dot over a variable to represent a fluxion, which changed into essentially a spinoff of the variable with recognize to time or another variable.

whilst the time period "fluxions" is not commonly used, Newton's work laid the muse for the development of calculus, a mathematical field this is nonetheless extensively used today in fields together with physics, engineering, and economics.

Learn more about derivative:-

https://brainly.com/question/30770472

#SPJ1

write the parametric equations of a line with rectangular equation and passing through the point (1,2)

Answers

The parametric equations for the line passing through the point (1,2) are: x = t and y = 2

To find the parametric equations of a line with a rectangular equation, we can first convert the rectangular equation into slope-intercept form and then use the slope and y-intercept to create the parametric equations.

Since we don't have a specific rectangular equation given in the question, I'll assume a general form of:

y = mx + b

where m is the slope and b is the y-intercept.

To find the slope, we can use the fact that the line passes through the point (1,2). We can choose any other point on the line to calculate the slope, but using the given point simplifies the calculation. We'll substitute x=1 and y=2 into the equation:

2 = m(1) + b

Simplifying:

2 = m + b

To find the y-intercept, we can substitute x=0 into the equation and use the fact that y=0 (since the line passes through the x-axis):

0 = m(0) + b

Simplifying:

b = 0

Now we have both m and b, so we can write the slope-intercept equation for the line:

y = mx

Substituting the value of b:

y = mx + 0

Simplifying:

y = mx

Finally, we can create the parametric equations using the parameter t:

x = t
y = mt

Substituting the value of m:

x = t
y = (2/t) * t

Simplifying:

x = t
y = 2

So the parametric equations for the line passing through the point (1,2) are:

x = t
y = 2

To know more about parametric equations  click on below link :

https://brainly.com/question/28537985#

#SPJ11

identify the next three terms in the geometric sequence. 8, 24, 72, 216,... 512, 1024, 4832 512, 1536, 4608 648, 1944, 3888 648, 1944, 5832

Answers

In order to determine the following three terms in the geometric series [tex]8, 24, 72, 216[/tex],..., we must first determine the common-ratio (r):

A geometric-sequence is a set of integers where each phrase following the first is obtained by multiplying the term before it by a fixed quantity known as the common- ratio (r).

Mathematical, scientific, and financial fields all use geometric sequences extensively. They can be used, for instance, to simulate population increase, radioactive isotope decay, asset depreciation, and the calculation of compound interest.

[tex]r = (24 / 8)[/tex]

[tex]r = (72 / 24)[/tex]

[tex]r = (72 / 24)[/tex]

[tex]r = (72 / 24)[/tex]

Consequently, the sequence's common ratio is [tex]3[/tex].

Following three terms are:

[tex]648 (216 * 3)[/tex]

[tex]648 (216 * 3)[/tex]

The finished sequence is thus [tex]8, 24, 72, 216, 648, 1944[/tex], and[tex]5832.[/tex]

To know more about geometric-sequence visit:

https://brainly.com/question/1354225

#SPJ4

PLEASE HELP!!! ASAP!!

Answers

Answer: its B

Step-by-step explanation:

Other Questions
Holding large amounts of bank capital helps prevent bank failures because. A star is in hydrostatic equilibrium when the outward push of pressure due to core burning is exactly in balance with the inward pull of gravity. When the hydrogen in a stars core has been used up, burning ceases, and gravity and pressure are no longer in balance. This causes the star to undergo significant changes. Which of the following evolutionary changes would bring a star back into hydrostatic equilibrium?. Mitosis and meiosis are cell division mechanisms that lead to different numbers of daughter cells. Which explanation best describes how these two processes maintain genetic continuity?. (L1) Given: ABC;BDAC;AB=BC;AC=8 inchesWhat is the length of AD?By which Theorem? The greatest danger or risk of an unsound best-cost provider strategy isA-that buyers will be highly skeptical about paying a relatively low price for upscale attributes/features.B-not establishing strong alliances and partnerships with key suppliers.C-that low-cost leaders will be able to steal away some customers on the basis of a lower price, and high-end differentiators will be able to steal away customers with the appeal of better product attributes.D- that it will be unable to achieve top-notch quality at a rock-bottom cost.E- becoming too highly integrated and not relying enough on outsourcing.Expert Answer100 for this experiment we assumed the calorimeter was a perfect insulator (no heat was lost to the surroundings). is this a good assumption? explain your answer. *****Which would have one or more coordinate covalent bond: BCl3, NH4+, PCl5, AlCl6-3, BeCl2, SbCl6-, PCl3, TeF4, ClO4-. select all the apply: which of the following statements is true about the parasympathetic nervous system? How does carotid sinus massage help a person in PSVT recover? Pushing unacceptable id impulses back into the unconscious mind is called _____. the raven by edaar allen poe who is the speaker what is his state or mind how does the raven mirror the speaker mental's state who do they think they are? i spent the best years of my life at this place and they think they can just fire me like that like trash? What fish is native to the shallow tropical waters of the western atlantic?. The yield to maturity on a bond is:I. above the coupon rate when the bond sells at a discount, and below the coupon rate when the bond sells at a premiumII. the discount rate that will set the present value of the payments equal to the bond priceIII. equal to the true compound return on investment only if all interest payments received are reinvested at the yield to maturityA. I onlyB. II onlyC. I and II onlyD. I, II and III which statement is not true about group f/64? a. group f/64 photographers were highly political. b. group f/64 photographers liked to use large-format view cameras. c. group f/64 photographers often used the greatest depth of field. d. group f/64 photographers liked to take close-up photographs. if the demand for hair gel increases, the effect on the hair gel manufacturing job market will be to group of answer choices decrease the demand for labor and reduce equilibrium wages. have no impact on equilibrium wages. increase the demand for labor and increase equilibrium wages. reduce the supply of labor and increase equilibrium wages. The theory of behavior in which people who associate with some groups learn an excess of definitions of deviance, increasing the likelihood that they will become deviant is ________. which of the following control procedures best protect sensitive information about employee financial data from unauthorized viewing by the employees who process and update payroll? When you notice these warning signs, get off the road. Do not depend on warning signs because sometimes microsleeps occur without any warning. You cannot predict when you will fall asleep at the wheel.T/F How did the california gold rush lead to the expansion of cities?.