Many drivers of cars that can run on regular gas instead buy premium gas in the belief that they will get better gas mileage (miles per gallon). To test that belief, a sample of 10 cars was obtained from a company fleet where all the cars can run on regular gas. Each car is filled first with either regular or premium gasoline, as decided by a coin toss, and the mileage for that full tank of gas is recorded. The mileage is again recorded for the same cars with a full tank of gas of the other kind of gasoline. The car drivers were unaware that they were participating in an experiment. Research Question: Does the data suggest, on the average, that the cars had a higher gas mileage (in miles per gallon) with premium gas when compared to regular gas? This is an example of paired data because there are two recorded measurements for each [answer1].  On the average, 2.0 [answer2] miles per gallon was achieved with regular gas.  When using the paired t procedure, we [answer3] successful in reducing variation between the types of gasoline, because the standard deviation for the differences: sd = [answer4] miles per gallon is [answer5] the standard deviations found with the original two samples for Premium and Regular gas.

Researchers are interested in determining if there is an association between the number of hours a student works in a week and the number of classes they miss in a week.  Assume data was collected and they found a correlation of 0.623. Using this information, they calculated a p-value of 0.014. Determine whether each of the statements below is true or false.

A randomly selected sample of n = 8 smart watch users completed a survey. These smart watch users indicated that they stood for an average of 16 minutes per day with a standard deviation of 4 minutes per day. The calculated standard error of the mean is 1.41 minutes per day. Assume that all conditions are met to use the theoretical t distribution for inference.  Which is the correct 90% confidence interval for the average minutes stood per day by Smart-watch users?

This table includes the total number of medals won at the 2022 Winter Olympics for countries that won at least one medal. Country Total Medals Won Country Total Medals Won 1. Norway 37 16. Slovenia  7 2. Republic of China 32 17. Australia  4 3. Germany 27 18. New Zealand  3 4. Canada 26 19. Hungary  3 5. United States 25 20. Great Britain  2 6. Sweden 18 21. Belgium  2 7. Austria 18  22. Czech Republic  2 8. Japan 18 23. Slovakia  2 9. Netherlands 17 24. Belarus  2 10. Italy 17 25. Spain  1 11. China 15 26. Ukraine  1 12. Switzerland 15 27. Estonia  1 13. France 15 28.Latvia  1 14. South Korea  9 29. Poland  1 15. Finland  8 The sample mean is 11.31 medals  Match the attribute of the sample with the appropriate answer.

Consider each scenario and decide which statistical procedure should be used to answer the question. Scenario A: On average, do Stat 200 students spend more time on social media (hours/week) when compared to studying (hours/week). A difference in hours/week was computed for each student when considering the two samples.  Scenario B: On average, are the weights (in pounds) for carry-on luggage of adult male passengers higher in the winter months when compared to summer months. A random sample of 100 male passengers who traveled in the winter and a random sample of 100 males passengers who traveled in the summer were obtained.  The weight of the carry-on luggage in pounds was obtained. With Scenario A, we should use the [answer1] procedure.   With Scenario B, we should use the [answer2] procedure.

Consider the StatKey output below that provides a bootstrap distribution for the difference in proportions:   Use all provided information. The normal approximation of this bootstrap distribution is: N(

A scientific study conducted in 2017 wants to determine if a person drinking soda attracts more flies than a person drinking water.  The study looked at 62 adult volunteers who were randomly assigned to consume either soda or water. Their attractiveness to flies was measured by counting how many flies approached each person in a one-hour period.  Of the 31 adults assigned to soda group, they found that the average number of flies was 132.  With the 31 adults assigned to water group, they found the average number of flies was 130. The correct null and alternative hypotheses for this situation would be: Ho:[answer1][answer2][answer3] Ha:[answer4][answer5][answer6] Assuming the relevant p-value for this test was 0.3523, complete the conclusion below: We [answer7] the null hypothesis.  We [answer8] convincing evidence that there is a difference in the mean number of flies that were attracted when comparing soda and water drinkers.

Assume we are testing the hypotheses below, using a sample of size n=25: H0: p = 0.50   Ha: p

Assume a researcher performs a hypothesis test and uses the below screenshot from StatKey to calculate the p-value: Look at all of the provided information on the graph when answering this question.  The alternative hypothesis of Ha: [answer1] is the only possibility because the p-value was obtained from the theoretical [answer2] distribution and the test is [answer3].

Consider the three histograms shown below. Each are based on n = 900 observations.   Match the histograms to the corresponding boxplots.