An SAT prep course claims to improve the test score of students. The table below shows the scores for seven students the first two times they took the verbal SAT. Before taking the SAT for the second time, each student took a course to try to improve his or her verbal SAT scores. Do these results support the claim that the SAT prep course improves the students' verbal SAT scores?

Let d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course)d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course). Use a significance level of α=0.01 for the test. Assume that the verbal SAT scores are normally distributed for the population of students both before and after taking the SAT prep course.

Copy Data

Step 1 of 5:

State the null and alternative hypotheses for the test.

Step 2 of 5:

Find the value of the standard deviation of the paired differences. Round your answer to one decimal place.

Step 3 of 5:

Compute the value of the test statistic. Round your answer to three decimal places.

Step 4 of 5:

Determine the decision rule for rejecting the null hypothesis H0. Round the numerical portion of your answer to three decimal places.

Step 5 of 5:

Make the decision for the hypothesis test.

For all of the following questions 20.00 mL of 0.195 M HBr is titrated with 0.200 M KOH.
Region 1: Initial pH: Before any titrant is added to our starting material
What is the concentration of H+ at this point in the titration?
M

What is the pH based on this H+ ion concentration?

Region 2: Before the Equivalence Point 5.68 mL of the 0.200 M KOH has been added to the starting material.
Complete the BCA table below at this point in the titration. (Be sure to use moles)
HBr (aq)   KOH (aq)   ?   H2O (l)   KBr (aq)
B               NA  
C               NA  
A               NA  
From the moles of HBr left after the reaction with KOH what will the pH be at this point in the titration?

Region 3: Equivalence Point
What volume of the titrant has been added to the starting material at the equivalence point for this titration?
mL

At the equivalence point an equal number of moles of OH- and H+ have reacted, producing a solution of water and salt. What affects the pH at this point for a strong-acid/strong-base titration?
   The acidity of the salt cation
   The basicity of the salt anion
   The auto-ionization of water
   None of these

Region 4: After the Equivalence Point 31.31 mL of the 0.200 M KOH has been added to the starting material
Complete the BCA table below at this point in the titration. (Use moles)
HBr (aq)   KOH (aq)   ?   H2O (l)   KBr (aq)
B               NA  
C               NA  
A               NA  
From the moles of KOH remaining after the reaction with HBr what is the pOH at this point in the titration?

Calculate the pH of the solution from the pOH found in the previous step

An SAT prep course claims to improve the test score of students. The table below shows the scores for seven students the first two times they took the verbal SAT. Before taking the SAT for the second time, each student took a course to try to improve his or her verbal SAT scores. Do these results support the claim that the SAT prep course improves the students' verbal SAT scores?

Let d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course)d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course). Use a significance level of α=0.1 for the test. Assume that the verbal SAT scores are normally distributed for the population of students both before and after taking the SAT prep course.

Student   Score on first SAT   Score on second SAT
1   570   620
2   500   540
3   500   520
4   380   440
5   430   470
6   360   380
7   360   410

Step 1 of 5:

State the null and alternative hypotheses for the test.

Step 2 of 5:

Find the value of the standard deviation of the paired differences. Round your answer to one decimal place.

Step 3 of 5:

Compute the value of the test statistic. Round your answer to three decimal places.

Step 4 of 5:

Determine the decision rule for rejecting the null hypothesis H0H0. Round the numerical portion of your answer to three decimal places.

Step 5 of 5:

Make the decision for the hypothesis test.

Data on the rate at which a volatile liquid will spread across a surface are in the table. Complete parts athrough

c.

Mass (Pounds): 6.62, 5.96, 5.47, 4.85, 4.38, 4.05, 3.61, 3.09, 2.74 ,2.48, 2.23, 1.56, 0.94, 0.18, 0.00

Find a 98​% confidence interval for the mean mass of all spills with an elapsed time of 56minutes. Interpret the result.

What is the confidence​ interval?

(    ),(   )

​(Round to three decimal places as​ needed.)

Interpret the result. Choose the correct answer below.

A. We are 98​% confident that the interval will contain 56minutes.

B. We are 98​% confident that the interval will contain the mean mass of the spill before 56minutes has passed.

C. We are 98​% confident that the interval will not contain the mean mass of the spill at

56minutes.

D. We are 98​% confident that the interval will contain the mean mass of the spill after 56minutes.

b.Find a 98​% prediction interval for the mass of a single spill with an elapsed time of

56minutes. Interpret the result.

What is the prediction​ interval?

(.   ),(.  )

​(Round to three decimal places as​ needed.)

Interpret the result. Choose the correct answer below.

A.We are 98​% confident that the interval will contain the mass of the spill after 56minutes.

B.We are 98​% confident that the interval will contain 56minutes.

C.We are 98​% confident that the interval will contain the mass of the spill before 56minutes has passed.

D.We are 98​% confident that the interval will not contain the mass of the spill after 56minutes.

c.Compare the​ intervals, parts aand

b.

Which interval is​ wider? Will this always be the​ case? Explain. Fill in the blanks below.

The (prediction/confidence/neither) interval is wider. This (will/will not) always be the case because the error of this interval is the (random error/ sum of two errors/neither)

An SAT prep course claims to improve the test score of students. The table below shows the scores for seven students the first two times they took the verbal SAT. Before taking the SAT for the second time, each student took a course to try to improve his or her verbal SAT scores. Do these results support the claim that the SAT prep course improves the students' verbal SAT scores?

Let d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course)d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course). Use a significance level of α=0.05for the test. Assume that the verbal SAT scores are normally distributed for the population of students both before and after taking the SAT prep course.

1 of 5: State the null and alternative hypotheses for the test

Step 2 of 5: Find the value of the standard deviation of the paired differences. Round your answer to one decimal place.

Step 3 of 5: Compute the value of the test statistic. Round your answer to three decimal places.

Step 4 of 5: Determine the decision rule for rejecting the null hypothesis H0. Round the numerical portion of your answer to three decimal places.

Step 5 of 5: Make the decision for the hypothesis test. Reject or Fail to Reject

An SAT prep course claims to improve the test score of students. The table below shows the scores for seven students the first two times they took the verbal SAT. Before taking the SAT for the second time, each student took a course to try to improve his or her verbal SAT scores. Do these results support the claim that the SAT prep course improves the students' verbal SAT scores?

Let d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course)d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course). Use a significance level of α=0.01 for the test. Assume that the verbal SAT scores are normally distributed for the population of students both before and after taking the SAT prep course.

Step 1 of 5: State the null and alternative hypotheses for the test.

Step 2 of 5: Find the value of the standard deviation of the paired differences. Round your answer to one decimal place

Step 3 of 5: Compute the value of the test statistic. Round your answer to three decimal places.

Step 4 of 5: Determine the decision rule for rejecting the null hypothesis H0. Round the numerical portion of your answer to three decimal places.

Reject H0 if (t, ItI) (<,>) ____________

Step 5 of 5: Make the decision for the hypothesis test. (Reject or Fail to Reject Null Hypothesis)

An SAT prep course claims to improve the test score of students. The table below shows the scores for seven students the first two times they took the verbal SAT. Before taking the SAT for the second time, each student took a course to try to improve his or her verbal SAT scores. Do these results support the claim that the SAT prep course improves the students' verbal SAT scores?

Let d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course)d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course). Use a significance level of α=0.05 for the test. Assume that the verbal SAT scores are normally distributed for the population of students both before and after taking the SAT prep course.

Student   Score on first SAT   Score on second SAT
1   450 490
2   470   520
3   540   590
4   550   600
5   570   610
6   450   470
7   370   410

Step 1 of 5: State the null and alternative hypotheses for the test.

Step 2 of 5: Find the value of the standard deviation of the paired differences. Round your answer to one decimal place.

Step 3 of 5: Compute the value of the test statistic. Round your answer to three decimal places.

Step 4 of 5: Determine the decision rule for rejecting the null hypothesis H0. Round the numerical portion of your answer to three decimal places.

Step 5 of 5: Make the decision for the hypothesis test.

An experimenter interested in the causes of headaches suspects that much of the discomfort people suffer is from muscle tension. She believes that if people could relax the muscles in the head and neck region, the pain of a headache would decrease. Nine subjects are randomly selected from a headache pain clinic and asked to keep track of the number of headaches experienced over a two week period (baseline measurement). The subjects then completed a 6-week seminar in biofeedback training to learn how to relax the muscles in their head and neck. After completing the seminar, the subjects were then asked to record the number of headaches they experienced over a two week period using their new biofeedback skills. The number of headaches reported by subjects before and after the biofeedback training seminar are reported below.

Before Seminar: 17 13 6 5 5 10 8 6 7

After Seminar: 3 7 2 3 6 2 1 0 2

a. Describe (1) the independent variable and its levels, and (2) the dependent variable and its scale of measurement.

b. Describe the null and alternative hypotheses for the study described.

c. Using Excel, conduct a statistical test of the null hypothesis at p = .05. Be sure to properly state your statistical conclusion.

d. Provide an interpretation of your statistical conclusion in part C.

e. What type of statistical error might you have made in part C?

f. Obtain the 95% confidence interval using the obtained statistic.

g. Provide an interpretation of the confidence interval obtained in part f.

h. Does the confidence interval obtained support your statistical conclusion? Explain your answer.

An SAT prep course claims to improve the test score of students. The table below shows the scores for seven students the first two times they took the verbal SAT. Before taking the SAT for the second time, each student took a course to try to improve his or her verbal SAT scores. Do these results support the claim that the SAT prep course improves the students' verbal SAT scores?

Let d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course)d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course). Use a significance level of α=0.05 for the test. Assume that the verbal SAT scores are normally distributed for the population of students both before and after taking the SAT prep course.

Student   Score on first SAT   Score on second SAT
1   570   600
2   410   500
3   450   510
4   440   520
5   550   570
6   420   450
7   370   430

Step 1 of 5: State the null and alternative hypotheses for the test.

Step 2 of 5: Find the value of the standard deviation of the paired differences. Round your answer to one decimal place.

Step 3 of 5: Compute the value of the test statistic. Round your answer to three decimal places.

Step 4 of 5: Determine the decision rule for rejecting the null hypothesis H0. Round the numerical portion of your answer to three decimal places.

Step 5 of 5: Make the decision for the hypothesis test.