You measure 40 textbooks' weights, and find they have a mean weight of 45 ounces. Assume the population standard deviation is 7.5 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight.
Solution:
Confidence interval for Population mean is given as below:
Confidence interval = Xbar ± Z*σ/sqrt(n)
From given data, we have
Xbar = 45
σ = 7.5
n = 40
Confidence level = 95%
Critical Z value = 1.96
(by using z-table)
Confidence interval = Xbar ± Z*σ/sqrt(n)
Confidence interval = 45 ± 1.96*7.5/sqrt(40)
Confidence interval = 45 ± 2.3242
Lower limit = 45 - 2.3242 = 42.68
Upper limit = 45 + 2.3242 = 47.32
Confidence interval = (42.68, 47.32)
42.68 ounce < µ < 47.32 ounce
You measure 40 textbooks' weights, and find they have a mean weight of 45 ounces. Assume...
You measure 45 textbooks' weights, and find they have a mean weight of 68 ounces. Assume the population standard deviation is 5.4 ounces. Based on this, construct a 90% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places <<
You measure 45 textbooks' weights, and find they have a mean weight of 73 ounces. Assume the population standard deviation is 11 ounces. Based on this, construct a 90% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places < μ <
You measure 38 textbooks' weights, and find they have a mean weight of 53 ounces. Assume the population standard deviation is 10 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight.
You measure 24 textbooks' weights, and find they have a mean weight of 33 ounces. Assume the population standard deviation is 13.2 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places
You measure 49 textbooks' weights, and find they have a mean weight of 59 ounces. Assume the population standard deviation is 9.7 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places
You measure 28 textbooks' weights, and find they have a mean weight of 76 ounces. Assume the population standard deviation is 12.3 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places
You measure 24 textbooks' weights, and find they have a mean weight of 47 ounces. Assume the population standard deviation is 3.6 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places
You measure 31 textbooks' weights, and find they have a mean weight of 38 ounces. Assume the population standard deviation is 8.4 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight. Round endpoints to 2 decimal places. Select an answer ounces
You measure 35 textbooks' weights, and find they have a mean weight of 32 ounces. Assume the population standard deviation is 10.4 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places ____________< μ <_________
You measure 27 textbooks' weights, and find they have a mean weight of 31 ounces. Assume the population standard deviation is 8.7 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places < μ μ < License