Post a New Question

statistics

posted by .

A 90% confidence interval for a population mean based on 144 observations is computed to be (2.7,3.4). How many observations must be made so that 90% confidence interval will specify the mean to within ± 0.2

  • statistics -

    n=140

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

    Consider a 95% confidence interval for a population mean constructed from a random sample of 250 observations taken from a Normal population. Sigma is known to be 14. If we were to construct another 95% confidence interval, this time …
  3. statistics

    Consider a 95% confidence interval for a population mean constructed from a random sample of 250 observations taken from a Normal population. Sigma is known to be 14. If we were to construct another 95% confidence interval, this time …
  4. 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?
  5. Statistics

    A 95% confidence interval for a population mean, ?
  6. Statistics

    Suppose x has a mound-shaped distribution with sigma = 9 . A random sample of size 36 has sample mean 20. Is it appropriate to use a normal distribution to compute a confidence interval for the population mean m?
  7. Statistics

    Multiple Choice Which of the following statements is true about the 95% confidence interval of the average of a sample?
  8. 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 …
  9. Statistics

    A random sample of 90 observations produced a mean that = 25.9 and a standard deviation s =2.4 (a)Find a 95% confidence interval for u (b)Find a 90% confidence interval for u (c)Find a 99% confidence interval for u (Use integers or …
  10. Statistics

    A confidence interval for a population mean has a margin of error of 3.1. a)Determine the length of the confidence interval. b)If the sample mean is 56.7, obtain the confidence interval.

More Similar Questions

Post a New Question