500 câu trắc nghiệm Kinh tế lượng – 6C
Find the margin of error for the 95% confidence interval used to estimate the population proportion.
7) In a survey of 5400 T.V. viewers, 30% said they watch network news programs.
○ 0.00915
○ 0.0140
● 0.0122
○ 0.0160
Use the given degree of confidence and sample data to construct a confidence interval for the population
proportion p.
8) n = 89, x = 25; 98 percent
○ 0.187 < p < 0.375
○ 0.169 < p < 0.393
● 0.170 < p < 0.392
○ 0.188 < p < 0.374
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.
9) Margin of error: 0.04; confidence level: 90%; from a prior study, \({\hat p}\) is estimated by 0.19.
● 261
○ 783
○ 231
○ 10
Solve the problem.
10) 19 randomly picked people were asked if they rented or owned their own home, 18 said they rented. Obtain a point estimate of the true proportion of home owners.
○ 0.105
● 0.053
○ 0.486
○ 0.947
Use the given degree of confidence and sample data to construct a confidence interval for the population proportion p.
11) Of 225 employees selected randomly from one company, 18.67% of them commute by carpooling. Construct a 90% confidence interval for the true percentage of all employees of the company who carpool.
○ 13.6% < p < 23.8%
● 14.4% < p < 22.9%
○ 12.0% < p < 25.4%
○ 12.6% < p < 24.7%
Use the confidence level and sample data to find the margin of error E.
12) The duration of telephone calls directed by a local telephone company: s = 3.8 minutes, n = 401,
80 percent confidence.
○ 0.011 minutes
○ 0.006 minutes
● 0.244 minutes
○ 0.237 minutes
Use the confidence level and sample data to find a confidence interval for estimating the population \(\mu \).
13) A laboratory tested 81 chicken eggs and found that the mean amount of cholesterol was 204 milligrams with s = 10.2 milligrams. Construct a 95 percent confidence interval for the true mean cholesterol content, \(\mu \), of all such eggs.
● 202 < \(\mu \) < 206
○ 203 < \(\mu \) < 205
○ 201 < \(\mu \) < 207
○ 200 < \(\mu \) < 208