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6. Is there a difference in the average age that people get married in the United States and its close neighbor, Canada? Suppose a random sample of 30 Americans had an average age of marriage of 28 years with standard deviation 3 years. For a random sample of 30 Canadians, the average age was 30.1 years with standard deviation 3.3 years. (a) Construct a \( 95 \% \) confidence interval for the difference in average age of marriage between Canadians and Americans. (b) Interpret the interval. (c) Based on the interval, do you expect there to be evidence or little to no evidence for \( H_{a} \) : \( \mu_{1} \neq \mu_{2} \) ? Explain without conducting the hypothesis test.

The Adobe School District is hiring a vice principal and has interviewed four candidates: Anna (A), Bono (B), Clark (C), and David (D). The hiring committee has indicated their preferences. \( \binom{A C D B}{8}\binom{C B A D}{1}\binom{B C D A}{3}\binom{D B C A}{6} \) Who is the winner using the plurality method?

Consider an election with three candidates with the results: \( \binom{C B A}{2}\binom{A C B}{8}\binom{B A C}{7}\binom{B C A}{2} \) Who wins the election using the Borda count method?

105. Is sea level the same along all coastal regions? To examine this a sample of 12 coastal locations in the Gulf Coast had mean sea level 5.3953 m and standard deviation 2.2559 m . A sample of 17 locations along the eastern seaboard had mean 3.4028 m and standard deviation 1.036 m . We can assume the distribution of sea level is Normal. (a) What is the point estimate for the difference in mean sea level between the Gulf Coast and eastern seaboard? (b) What is the standard error of the difference in means? (c) What is the margin of error for a \( 90 \% \) confidence interval? (d) Construct and interpret the confidence interval for the difference in mean sea level between the Gulf Coast and the eastern seaboard. (e) Based on the interval, do you expect there to be evidence or little to no evidence for \( H_{a} \) : \( \mu_{1} \neq \mu_{2} \) ? Explain without conducting the hypothesis test.

The Adobe School District is hiring a vice principal and has interviewed four candidates: Anna (A), Bono (B) Clark (C), and David (D). The hiring committee has indicated theirbreferences. \( \binom{A C D B}{8}\binom{C B A D}{1}\binom{B C D A}{3}\binom{D B C A}{6} \) Who is the winner using the plurality method?

Consider an election with three candidates with the results: \( \binom{C B A}{2}\binom{A C B}{8}\binom{B A C}{7}\binom{B C A}{2} \) Who wins the election using the Borda count method?

16. Consider the grouped frequency table for students' weight in a certain school.

Exercice On a demandé à des élèves le nombre de films qu'ils ont vu au cinéma depuis la rentrée. Leurs réponses sont présentées dans le diagramme en bâtons ci-contre. 1. Que signifie lé sixième rectangle ? 2. Combien d'élèves ont été interrogés ? 3. Combien de films ces élèves ont-ils vu en moyenne? Préciser le calcul. 4. Déterminer l'étendue de cette série. 5. Déterminer le nombre médian de films vus. 6. Calculer le pourcentage des élèves qui ont vu au moins 4 films.

Exercice On a demandé à des élèves le nombre de films qu'ils ont vu au cinéma depuis la rentrée. Leurs réponses sont présentées dans le diagramme en bâtons ci-contre. 1. Que signifie lé sixième rectangle ? 2. Combien d'élèves ont été interrogés ? 3. Combien de films ces élèves ont-ils vu en moyenne? Préciser le calcul. 4. Déterminer l'étendue de cette série. 5. Déterminer le nombre médian de films vus. 6. Calculer le pourcentage des élèves qui ont vu au moins 4 films.

Page 47 of 55 Ruby surveyed a random sample of 90 employees at a company, and 15 said they have a gym membership. Based on the results of the survey, of the 600 total employees at the company, what is the expected number that have a gym membership? 100 150 150 105 150