A government official is in charge of allocating social programs throughout the city of Vancouver. He will decide where these social outreach programs should be located based on the percentage of residents living below the poverty line in each region of the city. He takes a simple random sample of 122 people living in Gastown and finds that 20 have an annual income that is below the poverty line. Suppose that the government official wants to re-estimate the population proportion and wishes for his 90% confidence interval to have a margin of error no larger than 0.03. How large a sample should he take to achieve this? Please carry answers to at least six decimal places in intermediate steps, and use at least 3 decimal places in your critical value. Sample size =

The researcher is concerned that older persons may not be knowledgeable of the COFLU-20. As such, he is interested in investigating the association between the age of the respondents and their knowledge level. Table 2 below shows the knowledge level of respondents, by age group. Table 2 (image included) Conduct a test, at the 5% level of significance, to determine whether the data provided sufficient evidence to conclude that an association exists between age group and knowledge level. State the hypotheses to be tested: H0: H1: state the degrees of freedom for this test the p-value for this test, given that the chi-square test statistic, c2, is 11.029. state the conclusion for the test. Give reason for your answer.

A health insurance company is looking at the use of its benefits by its members. It randomly selects 500 members for further study, and one of the pieces of information they collect is the amount the amount of money spent on prescription medications over the past year. The average amount among the 500 members is $600 and the SD is $1,000. A histogram of the amounts is quite skewed to the right, and 40 (8%) of the sampled members have spent $5000 or more on prescription medications in the past year. Calculate a 95%-confidence interval for the percentage of all members who have spent $5000 or more on prescription medications in the last year.

Anita's, a fast-food chain specializing in hot dogs and garlic fries, keeps track of the proportion of its customers who decide to eat in the restaurant (as opposed to ordering the food "to go"), so it can make decisions regarding the possible construction of in-store play areas, the attendance of its mascot Sammy at the franchise locations, and so on. Anita's reports that 45% of its customers order their food to go. If this proportion is correct, what is the probability that, in a random sample of 5 customers at Anita's, exactly 3 order their food to go?

A sociologist is comparing the proportion of teenage boys who receive a text message at least once an hour to the percentage of teenage girls who do.  She has collected data from 150 men and 150 women.  Which of the following is not a condition that the sociologist should check before creating a confidence interval for the difference in population proportions?

An epidemiologist is worried about the prevalence of the flu in East Vancouver and the potential shortage of vaccines for the area. She will need to provide a recommendation for how to allocate the vaccines appropriately across the city. She takes a simple random sample of 332 people living in East Vancouver and finds that 36 have recently had the flu. Suppose that the epidemiologist wants to re-estimate the population proportion and wishes for her 95% confidence interval to have a margin of error no larger than 0.04. How large a sample should she take to achieve this? Please carry answers to at least six decimal places in intermediate steps, and use at least 3 decimal places in your critical value. Sample size =

Ellie and Alec are each attempting to estimate the proportion of coffee drinkers who consume more than one cup of coffee per day. They each obtain a random sample of coffee drinkers, and, in each sample, the proportion who drink more than one cup of coffee per day is 0.40. Ellie and Alec each use their sample data to construct a confidence interval. Ellie’s interval is from 0.286 to 0.514, and Alec’s interval is from 0.346 to 0.474. One of these intervals was computed correctly, but the other was not. Which interval must be incorrect? A. Ellie’s interval must be incorrect. B. Alec’s interval must be incorrect. C. It’s impossible to answer this question without knowing the level of confidence used for each interval. D. It’s impossible to answer this question without knowing the sample sizes. E. It’s impossible to answer this question without knowing the sample sizes or the level of confidence used for each interval.