On a television show, eight contestants try to lose the highest percentage of weight in order to win a cash prize. As part of the show, the contestants are timed as they run an obstacle course. The table shows the times (in seconds) of the contestants at the beginning of the season and at the end of the season. At

α=0.05 is there enough evidence to support the claim that the contestants' times have changed? Assume the samples are random and dependent, and the population is normally distributed. Complete parts (a) through (e) below.

1. Identify the claim and Ho and Ha

            What is the claim?

Let μd be the hypothesized mean of the difference in the times (beginning− end). What are Ho and Ha?

B. Find the critical value(s) and identify the rejection region(s).

C. Calculate dBAR and Sd.

(d) Find the standardized test statistic t.

E. (e) Decide whether to reject or fail to reject the null hypothesis and interpret the decision in the context of the original claim.

________the null hypothesis. There ____ enough evidence to _____the claim that the contestants times have _____.

The home run percentage is the number of home runs per 100 times at bat. A random sample of 43 professional baseball players gave the following data for home run percentages.

(a) Use a calculator with mean and standard deviation keys to find x and s. (Round your answers to two decimal places.)

(b) Compute a 90% confidence interval for the population mean μ of home run percentages for all professional baseball players. Hint: If you use the Student's t distribution table, be sure to use the closest d.f. that is smaller. (Round your answers to two decimal places.)

(c) Compute a 99% confidence interval for the population mean μ of home run percentages for all professional baseball players. (Round your answers to two decimal places.)

The Centers for Disease Control reported the percentage of people 18 years of age and older who smoke (CDC website, December 14, 2014). Suppose that a study designed to collect new data on smokers and nonsmokers uses a preliminary estimate of the proportion who smoke of .33.

a. How large a sample should be taken to estimate the proportion of smokers in the population with a margin of error of .02 (to the nearest whole number)? Use 95% confidence.

b. Assume that the study uses your sample size recommendation in part (a) and finds 520 smokers. What is the point estimate of the proportion of smokers in the population (to 4 decimals)?

c. What is the 95% confidence interval for the proportion of smokers in the population (to 4 decimals)?

Let x be a random variable that represents the percentage of successful free throws a professional basketball player makes in a season. Let y be a random variable that represents the percentage of successful field goals a professional basketball player makes in a season. A random sample of n = 6 professional basketball players gave the following information.

x   67   64   75   86   73   73
y   44   40   48   51   44   51

(a) Find Σx, Σy, Σx2, Σy2, Σxy, and r. (Round r to three decimal places.)
Σx =   438
Σy =   278
Σx2 =   32264
Σy2 =   12978
Σxy =   20429
r =  

(b) Use a 5% level of significance to test the claim that ρ > 0. (Round your answers to two decimal places.)
t =  
critical t =  

Conclusion
A- Reject the null hypothesis, there is sufficient evidence that ρ > 0.
B-Reject the null hypothesis, there is insufficient evidence that ρ > 0.
C-Fail to reject the null hypothesis, there is insufficient evidence that ρ > 0.
D-Fail to reject the null hypothesis, there is sufficient evidence that ρ > 0.

(c) Find Se, a, b, and x. (Round your answers to four decimal places.)
Se =  
a =  
b =  
x =  

(d) Find the predicted percentage ŷ of successful field goals for a player with x = 80% successful free throws. (Round your answer to two decimal places.)

(e) Find a 90% confidence interval for y when x = 80. (Round your answers to one decimal place.)
lower limit = ?
upper limit =?

(f) Use a 5% level of significance to test the claim that β > 0. (Round your answers to two decimal places.)
t =  
critical t =  

Conclusion
A-Reject the null hypothesis, there is sufficient evidence that β > 0.
B-Reject the null hypothesis, there is insufficient evidence that β > 0.
C-Fail to reject the null hypothesis, there is insufficient evidence that β > 0.
D-Fail to reject the null hypothesis, there is sufficient evidence that β > 0.

A pollster would like to survey 500 students to determine the percentage that would vote for Ben Carson. If the pollster surveyed 500 students who worked directly with Carson will the results be meaningful to depict the thinking of the entire US population of students? Answer yes or no with explanation.

Why was Marilyn Vos Savant's calculation of having breast cancer given a positive mammogram test flawed?

A. Hubble telescope sees a dime sized view of the universe which represents an accurate sample

B. Jhon Hickley is insane

C. Fibonacciseries appears eveerywhere in nature

D.Women who get mammograms have a higher probability of breast cancer than the random American and Marilyn used the random American probabillity in her calculation.

The following data represents the winning percentage (the number of wins out of 162 games in a season) as well as the teams Earned Run Average, or ERA. The ERA is a pitching statistic. The lower the ERA, the less runs an opponent will score per game. Smaller ERA's reflect (i) a good pitching staff and (ii) a good team defense. You are to investigate the relationship between a team's winning percentage - Y, and its Earned Run Average (ERA) - X. Winning Proportion - Y Earned Run Average (ERA) - X 0.623457 3.13 0.512346 3.97 0.635802 3.68 0.604938 3.92 0.518519 4.00 0.580247 4.12 0.413580 4.29 0.407407 4.62 0.462963 3.89 0.450617 5.20 0.487654 4.36 0.456790 4.91 0.574047 3.75 (a) Using MINITAB, create a scatter-plot of the data. What can you conclude from this scatter-plot? A. There is not a linear relationship between the a teams winning percentage and its ERA. B. There is a positive linear relationship between a teams winning percentage and its ERA. C. There is a negative linear relationship between a teams winning percentage and its ERA. (b) Use MINITAB to find the least squares estimate of the linear model that expressed a teams winning percentage as a linear function of is ERA. Use four decimals in each of your answers. Yˆi = Xi (c) Find the value of the coefficient of determination, then complete its interpretation. r2= (use four decimals) The percentage of in that is explained by its linear relationship with is equation editorEquation Editor %. (d) Interpret the meaning of the slope term in the estimate of the linear model, in the context of the data. As a teams increases by the teams will equation editorEquation Editor . (use four decimals) (e) A certain professional baseball team had an earned run average of 3.45 this past season. How many games out of 162 would you expect this team to win? Use two decimals in your answer. games won (f) The team mentioned in part (e) won 91 out of 162 games. Find the residual, using two decimals in your answer. ei=

The percentage of people who recycle their old phone books is 15.8% on average. If 240 people are randomly selected, what is the probability that more than 20% of them recycle their phone book?

Find the percentage of area under a normal curve between the mean and the given number of standard deviations from the mean. This problem can be solved using technology or the table for the standard normal curve from your text. 0.9 The percentage of area under the normal curve between the mean and 0.9 standard deviations from the mean is ...%

What is the percentage (%w/w) of lidocaine in a gel compounded by mixing 15 hg of 10% lidocaine gel, 30 dag of 25% lidocaine gel and 160,000 mcg of 15% lidocaine gel?