Suppose we do not know the population standard deviation. What is the margin of error when the standard error is 4, and the confidence coefficient is .98 and we are working with a sample of 35 observations?
here for (0.98 confidence interval and (n-1=34 )degree of freedom; critial t =2.441
therefore margin of error =t*Std error =4*2.441=9.764
Suppose we do not know the population standard deviation. What is the margin of error when...
Problem 6. Suppose that we know that the population standard deviation σ = 5. Then for a 90% confidence interval, how large should a sample be to estimate the population mean μ with a margin of error not exceeding 0.5?
When estimating a population mean by a sample mean, the margin of error does NOT depend on ______. A) The confidence level B) The sample mean C) The sample size D) The population standard deviation What is the sampling distribution of a statistic? A) The distribution of observations of the statistic for all possible sizes of samples from a population B) The distribution of all possible observations of the statistic for samples of a given size from a population C)...
Consider a population having a standard deviation equal to 9.96. We wish to estimate the mean of this population. (a) How large a random sample is needed to construct a 95% confidence interval for the mean of this population with a margin of error equal to 1? (Round your answer to the next whole number.) The random sample is units. (b) Suppose that we now take a random sample of the size we have determined in part a. If we...
Use the given margin of error, confidence level, and population standard deviation, sigmaσ, to find the minimum sample size required to estimate an unknown population mean, muμ. Margin of error: 1.91.9 inches, confidence level: 9595%, sigmaσequals=2.62.6 inches A confidence level of 9595% requires a mimimum sample size of nothing. (Round up to the nearest integer.)
A sample of 230 observations is selected from a normal population with a population standard deviation of 26. The sample mean is 18. (20 pts) Determine the standard error of the mean. Determine the 98% confidence interval for the population mean
1.Suppose we are estimating m. What happens to the required sample size as the desired margin of error increases while the population standard deviation and confidence level remain constant? 2. A quality control engineer would like to estimate the mean fill amount of a certain bottle-filling machine to within 0.05 liter. If we assume that the population standard deviation is 0.17 liters, how large of a sample is needed to estimate m with 98% confidence? 3.Assume the fill amount of...
For a population, the value of the standard deviation is 2.77. A random sample of 35 observations taken from this population produced the following data. 42 52 42 31 28 36 50 29 46 37 32 27 33 41 47 40 28 46 34 39 48 25 35 37 38 46 48 39 29 31 44 41 37 38 46 Round your answers to 2 decimal places. a. What is the point estimate of μ? _____ b. Make a 98%...
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Find the margin of error for a 95% confidence interval for estimating the population mean when the sample standard deviation equals 92, with a sample size of (a) 400,(b) 1800. What is the effect of the sample size? 2. The margin of error for a 95% confidence interval with a sample size of 400 is (Round to the nearest tenth as needed.) b. The margin of error for a 90% confidence interval with a sample size of 1600 is (Round...
Point Estimate ± Margin of Error Let’s assume the population standard deviation is 4. For a 95% CI for the mean find the minimum sample size such that the margin of error is 1.5.