500 câu trắc nghiệm Kinh tế lượng – 6B
Find the margin of error for the 95% confidence interval used to estimate the population proportion.
7) n = 390, x = 50
○ 0.0299
● 0.0332
○ 0.0398
○ 0.0349
Use the given degree of confidence and sample data to construct a confidence interval for the population
proportion p.
8) n = 60, x = 26; 95 percent
○ 0.327 < p < 0.539
● 0.308 < p < 0.558
○ 0.307 < p < 0.559
○ 0.328 < p < 0.538
Find the minimum sample size you should use to assure that your estimate of \({\hat p}\) will be within the required
margin of error around the population p.
Margin of error: 0.07; confidence level: 95%; from a prior study, \({\hat p}\) is estimated by the decimal equivalent of 91%.
○ 195
○ 57
○ 5
● 65
Solve the problem.
10) Find the point estimate of the true proportion of people who wear hearing aids if, in a random sample of 599 people, 43 people had hearing aids.
○ 0.070
○ 0.067
○ 0.928
● 0.072
Use the given degree of confidence and sample data to construct a confidence interval for the population proportion p.
11) Of 116 randomly selected adults, 34 were found to have high blood pressure. Construct a 95% confidence interval for the true percentage of all adults that have high blood pressure.
○ 22.3% < p < 36.3%
○ 18.4% < p < 40.2%
● 21.0% < p < 37.6%
○ 19.5% < p < 39.2%
Use the confidence level and sample data to find the margin of error E.
12) Replacement times for washing machines: 90% confidence; n = 44, x = 11.8 years, \(\sigma \) = 2.4 years
○ 6.6 years
○ 0.5 years
● 0.6 years
○ 0.1 years
Use the confidence level and sample data to find a confidence interval for estimating the population \(\mu \).
13) 39 packages are randomly selected from packages received by a parcel service. The sample has a mean weight of 15.3 pounds and a standard deviation of 1.9 pounds. What is the 95 percent confidence interval for the true mean weight, \(\mu \), of all packages received by the parcel service?
● 14.7 < \(\mu \) < 15.9
○ 14.5 < \(\mu \) < 16.1
○ 14.6 < \(\mu \)< 16.0
○ 14.8 < \(\mu \) < 15.8