In a recent study; it was found that 68 percent of college students drink heavily and drive. Assuming all conditions are met, a police chief wanting to enact an emergency protocol for DWI/DUI wants to know if the claim is accurate. He took a sample of 70 college students who drank and drove and found that 46 of those students had a high blood alcohol level. Can we claim that more than 68 percent of all college students drink heavily and drive at a significance level of five percent? .

A study was conducted to determine the proportion of people who dream in black and white instead of color. Among 285 people over the age of 55, 68 dream in black and white, and among 307 people under the age of 25, 14 dream in black and white. Use a 0.01 significance level to test the claim that the proportion of people over 55 who dream in black and white is greater than the proportion for those under 25. An explanation for the results is that those over the age of 55 grew up exposed to media that was displayed in black and white. Can these results be used to verify that explanation?   A. Yes. The results can be used to verify the given explanation because the difference in proportions is practically significant.   B. Yes. The results can be used to verify the given explanation because the difference in proportions is statistically significant.   C. No. The results speak to a possible difference between the proportions of people over 55 and under 25 who dream in…

5. A credit score is used by credit agencies (such as mortgage companies and banks) to assess the creditworthiness of individuals. Values range from 300 to 850, with a credit score over 700 considered to be a quality credit risk. According to a survey, the mean credit score is 702.9. A credit analyst wondered whether high-income individuals (incomes in excess of $100,000 per year) had higher credit scores. He obtained a random sample of 32 high-income individuals and found the sample mean credit score to be 719.1 with a standard deviation of 80.6. Conduct the appropriate test to determine if high-income individuals have higher credit scores at the a = 0.05 level of significance. State the null and alternative hypotheses. Ho: H (1) H: μ (2) (Type integers or decimals. Do not round.) Identify the t-statistic. to = (Round to two decimal places as needed.) Identify the P-value. P-value = (Round to three decimal places as needed.) Make a conclusion regarding the hypothesis. (3) the null…

A car wash is assessing the average wait time for its customers. The median wait time is 4 minutes. Does a customer who waits for 5 minutes represent an abnormal wait time? The customer who waits 5 minutes an abnormal case, because 50% of customers wait more than minutes.

Consider a drug testing company that provides a test for marijuana usage. Among 266 tested​ subjects, results from 27 subjects were wrong​ (either a false positive or a false​ negative). Use a 0.10 significance level to test the claim that less than 10 percent of the test results are wrong.

Most alpine skiers and snowboarders do not use helmets. Do helmetsreduce the risk of head injuries? A study in Norway compared skiers and snowboarders who suffered head injuries with a control group who were not injured. Of 578 injured subjects, 96 had worn a helmet. Of the 2992 in the control group, 656 wore helmets. Is helmet use less common among skiers and snowboarders who have head injuries?