Elementary Statistics

posted by .

1) Construct a confidence interval of the population proportion at the given level of confidence.
x=60,n=300, 99% confidence.
The 99% confidence interval is (_,_)

2) A researcher wishes to estimate the proportion of adults who have high-speed internet access. What size sample should be obtained if she wishes the estimate to be within 0.04 with 99% confidence if
a) she uses a previous estimate of 0.52?
b) she does not use any prior estimates?

  • Elementary Statistics (Partial) -

    1. 99% = mean ± 2.575 SEm

    SEm = SD/√n

    What is the value of the standard deviation (SD)?

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. statistics

    What do confidence intervals represent? What is the most controllable method of increasing the precision of or narrowing the confidence interval?
  2. Statistics

    Find the minimum sample size that should be chosen to assure that the proportion estimate p will be within the required margin of error, .06. Use a 95% confidence interval and a population proportion of .7. The critical value for a …
  3. Statistics

    Which of the following statements best describes the uncertainty associated with a 95% confidence interval for a population proportion, computed from a simple random sample?
  4. Statistics

    In a survey of 633 males ages 18-64, 395 say they have gone to the dentist in the past year. Construct 90% and 95% confidence intervals for the population proportion. Interpret the results and compare the widths of the confidence intervals. …
  5. Statistics

    These are the only ones that I am having problems with. Please help.. 8.You are given the sample mean and the sample standard deviation. Use this information to construct the 90% and the 95% confidence intervals for the population …
  6. Statistics

    Use the sample data and confidence level to construct the confidence interval estimate of the population proportion p. n=500, x=350, 90% confidence ?
  7. Statistics

    Use the sample data and confidence level to construct the confidence interval estimate of the population p....n=5200, x=4821, 99% confidence
  8. Statistics

    We have calculated a 95% confidence interval for a proportion and would prefer the confidence interval to be more precise, that is narrower. Using the same sample, we can narrow the confidence interval using which of the following?
  9. Statistics

    You are given the following information obtained from a random sample of 6 observations. Assume the population has a normal distribution. 13 14 17 14 17 15 a. What is the point estimate of µ?
  10. Statistics

    The standard deviation for a population is σ = 15.3. A sample of 36 observations selected from this population gave a mean equal to 74.8. a) Make a 90% confidence interval for μ b) Construct a 95% confidence interval for …

More Similar Questions