Reference no: EM133144272
1. A political candidate has asked you to conduct a poll to determine what percentage of people support him. If the candidate only wants a 0.5% margin of error at a 99% confidence level, what size of sample is needed? When finding the z-value, round it to four decimal places.
2. You want to obtain a sample to estimate a population proportion. At this point in time, you have no reasonable preliminary estimation for the population proportion. You would like to be 98% confident that you estimate is within 1% of the true population proportion. How large of a sample size is required?
3. A political candidate has asked you to conduct a poll to determine what percentage of people support her. If the candidate only wants a 5% margin of error at a 95% confidence level, what size of sample is needed? When finding the z-value, round it to four decimal places.
4. You want to obtain a sample to estimate a population proportion. Based on previous evidence, you believe the population proportion is approximately p = 0.14. You would like to be 99% confident that your estimate is within 5% of the true population proportion. How large of a sample size is required?
5. You want to obtain a sample to estimate a population proportion. Based on previous evidence, you believe the population proportion is approximately 81%. You would like to be 99% confident that your estimate is within 3.5% of the true population proportion. How large of a sample size is required?
6. You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately σ=59.3σ=59.3. You would like to be 99% confident that your estimate is within 5 of the true population mean. How large of a sample size is required?
7. You want to obtain a sample to estimate how much parents spend on their kids birthday parties. Based on previous study, you believe the population standard deviation is approximately σ=60.4σ=60.4 dollars. You would like to be 99% confident that your estimate is within 2.5 dollar(s) of average spending on the birthday parties. How many parents do you have to sample?