# Question: Cost of environmental restoration In a survey of 189 Scottish

Cost of environmental restoration: In a survey of 189 Scottish voters, 61 said they would be willing to pay additional taxes in order to restore the Affric forest.

a. Assuming that the 189 voters who responded constitute a random sample, construct a 99% confidence interval for the proportion of voters who would be willing to pay to restore the Affric forest.

b. Use the results from the sample of size 189 to estimate the sample size needed so that the 99% confidence interval will have a margin of error of 0.03.

c. Another survey is planned, in which voters will be asked whether they would be willing to pay in order to restore the Strathsprey forest. At this point, no estimate of this proportion is available. Find an estimate of the sample size needed so that interval will be 0.03.

a. Assuming that the 189 voters who responded constitute a random sample, construct a 99% confidence interval for the proportion of voters who would be willing to pay to restore the Affric forest.

b. Use the results from the sample of size 189 to estimate the sample size needed so that the 99% confidence interval will have a margin of error of 0.03.

c. Another survey is planned, in which voters will be asked whether they would be willing to pay in order to restore the Strathsprey forest. At this point, no estimate of this proportion is available. Find an estimate of the sample size needed so that interval will be 0.03.

## Answer to relevant Questions

More repairs: A sample a component showed the following costs: 93 97 27 79 81 87 a. Construct a 90% confidence interval for the mean cost of a repair for this type of component. b. Is there any evidence to suggest that this ...Explain the difference between confidence and probability. In Exercises 4 and 5, express the following survey results in terms of confidence intervals for p: Interpret calculator display: The following 11-84 Plus display presents the results of a hypothesis test a. Is this a test for a mean, a proportion, or a standard deviation? b. What are the null and alternate hypotheses? c. ...Power: A test of Ho: p = 100 versus If f. p > 100 will be made at a significance level of a = 0.01. The population standard deviation is a = 50 and the sample size is n = 75. Find the power of the test against the ...For some records, marked with a *. the record temperature occurred more than once. In these cases, only the most recent year is listed. Explain how this might cause the mean to be greater than the midpoint of 1942, even if ...Post your question