You measure 21 textbooks' weights, and find they have a mean
weight of 43 ounces. Assume the population standard deviation is
12.6 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 <
Solution :
Given that,
Point estimate = sample mean =
= 43
Population standard deviation =
= 12.6
Sample size = n =21
At 90% confidence level
= 1 - 90%
= 1 - 0.90 =0.10
/2
= 0.05
Z/2
= Z0.05 = 1.645( Using z table )
Margin of error = E = Z/2
* (
/n)
= 1.96* ( 12.6 / 21
)
E= 4.52
At 90% confidence interval estimate of the population mean
is,
- E <
<
+ E
43 - 4.52 <
< 43+ 4.52
38.48 <
< 47.52
You measure 21 textbooks' weights, and find they have a mean weight of 43 ounces. Assume...
You measure 33 textbooks' weights, and find they have a mean weight of 43 ounces. Assume the population standard deviation is 4.6 ounces. Based on this, construct a 90% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places License Question 4 of 7 Points possible: 1 This is attempt 1 of 1 .
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 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
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 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 48 textbooks' weights, and find they have a mean weight of 64 ounces. Assume the population standard deviation is 12.3 ounces. Based on this, construct a 90% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places < μμ <
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