A 90% confidence interval for a population mean was reported to be 153 to 159. If σ =15, what sample size was used in this study? (Round your answer to next whole number.)
For 90% confidence critical value of z is 1.645. The margin of error is
The sample size will be
Answer: 68
A 90% confidence interval for a population mean was reported to be 153 to 159. If...
A confidence interval for a population mean was reported to be to . If , what sample size was used in this study? (Round your answer to next whole number.)
A 95% confidence interval for a population mean was reported to be 150 to 160 . If standard deviation = 17, what sample size was used in this study? (Round your answer to next whole number.)
Assuming that the population is normally distributed, construct a 90% confidence interval for the population mean, based on the following sample size of n-6. 1, 2, 3, 4, 5, and 19 Change the number 19 to 6 and recalculate the confidence interval. Using these results, describe the effect of an outlier (that is, an extreme value) on the confidence interval. Find a 90% confidence interval for the population mean, using the formula or calculator. [ ] SHS (Round to two...
8.1.5 Question Help Determine the 95% confidence interval estimate for the population mean of a normal distribution given n = 100, o = 133, and x = 1,500 The 95% confidence interval for the population mean is from to (Round to two decimal places as needed. Use ascending order.) 8.1.14-T Question Help As a follow-up to a report on gas consumption, a consumer group conducted a study of SUV owners to estimate the mean mileage for their vehicles. A simple...
(3 points) A news report states that the 90% confidence interval for the mean number of daily calories consumed by participants in a medical study is (1930, 2170). Assume the population distribution for daily calories consumed is normally distributed and that the confidence interval was based on a simple random sample of 15 observations. Calculate the sample mean, the margin of error, and the sample standard deviation based on the stated confidence interval and the given sample size. Use the...
2) (3 points) A news report states that the 90% confidence interval for the mean number of daily calories consumed by participants in a medical study is (2020, 2160). Assume the population distribution for daily calories consumed is normally distributed and that the confidence interval was based on a simple random sample of 20 observations. Calculate the sample mean, the margin of error, and the sample standard deviation based on the stated confidence interval and the given sample size. Use...
Construct a 90% confidence interval to estimate the population mean using the data below. x=90 σ=15 n=40 N=400 The 90% confidence interval for the population mean is.
(3 points) A news report states that the 90% confidence interval for the mean number of daily calories consumed by participants in a medical study is (1750, 1980). Assume the population distribution for daily calories consumed is normally distributed and that the confidence interval was based on a simple random sample of 18 observations. Calculate the sample mean, the margin of error, and the sample standard deviation based on the stated confidence interval and the given sample size. Use the...
(3 points) A news report states that the 90% confidence interval for the mean number of daily calories consumed by participants in a medical study is (1920, 2070). Assume the population distribution for daily calories consumed is normally distributed and that the confidence interval was based on a simple random sample of 21 observations. Calculate the sample mean, the margin of error, and the sample standard deviation based on the stated confidence interval and the given sample size. Use the...
If a 90% confidence interval for the mean μ of a population is computed (using z) from a random sample of 25 subjects is found to be 42 ± 6.25. The population standard deviation σ is equal to: