|
|
Assume that a computer was used to generate the given confidence interval for the population mean, µ. Find the sample mean or margin of error as specified. 
|
| 3.23 |
| 3.550 |
| 3.610 |
| 3.490 |
|
|
|
(1129.7, 1145.1) Find the margin of error, E.
|
| 6.9 |
| 7.70 |
| 8.60 |
| 15.4 |
|
|
|
Use the given degree of confidence and sample data to find the margin of error in estimating the population mean. 
|
| 0.6 years |
| 5.6 years |
| 0.1 years |
| 0.7 years |
|
|
|
Use the given degree of confidence and sample data to construct a confidence interval for the population mean. 
|
| (541, 555) |
| (540, 556) |
| (543, 553) |
| (542, 554) |
|
|
|
Solve the problem. 
|
| 2.567 |
| 2.583 |
| 2.921 |
| 2.898 |
|
|
|
Given the sample statistics, determine if you should use the t distribution, normal distribution, or neither to construct a confidence interval for an estimate of. 
|
| Normal distribution |
| Neither |
| t distribution |
|
|
|
Solve the problem. 
|
| Exactly 95% |
| Smaller than 95% |
| Greater than 95% |
|
|
|
Find the necessary sample size. Scores on a certain test are normally distributed with a variance of 15. A researcher wishes to estimate the mean score achieved by all adults on the test. Find the sample size needed to assure with 98 percent confidence that the sample mean will not differ from the population mean by more than 4 units.
|
| 21 |
| 6 |
| 11 |
| 77 |
|
|
|
You wish to estimate the mean weight of machine components of a certain type and you require a 92% degree of confidence that the sample mean will be in error by no more than 0.008g. Find the sample size required. A pilot study showed that the population standard deviation is estimated to be 0.08g
|
| 199 |
| 18 |
| 15 |
| 307 |
|
|
|
Solve the problem. 
|
| 60 |
| 25 |
| 52 |
| 69 |
|
|
|
|
| 0.336 |
| 0.361 |
| 0.356 |
| 0.351 |
|
|
|
The following confidence interval is obtained for a population proportion, p: 0.408 < p < 0.432 Use these confidence interval limits to find the margin of error, E.
|
| 0.012 |
| 0.013 |
| 0.024 |
| 0.420 |
|
|
|
Use the given degree of confidence and sample data to construct a confidence interval for the population proportion p. n = 87, x = 26; 98 percent
|
| (0.185, 0.413) |
| (0.202, 0.396) |
| (0.180, 0.408) |
| (0.203, 0.395) |
|
|
|
When 258 college students are randomly selected and surveyed, it is found that 106 own a car. Find a 99% confidence interval for the true proportion of all college students who own a car.
|
| 0.351 < p < 0.471 |
| 0.332 < p < 0.490 |
| 0.339 < p < 0.482 |
| 0.360 < p < 0.461 |
|
|
|
|
| 13.1% < p < 30.4% |
| 12.2% < p < 31.3% |
| 15.7% < p < 27.9% |
| 14.5% < p < 29.0% |
|
|
|
Solve the problem. A researcher wishes to estimate the proportion of fish in a certain lake that is inedible due to pollution of the lake. How large a sample should be tested in order to be 96 percent confident that the true proportion of inedible fish is estimated to within 0.02?
|
| 26 |
| 2626 |
| 1282 |
| 2637 |
|
|
|
|
| 25.188 |
| 3.94 |
| 18.307 |
| 23.209 |
|
|
|
Use the given degree of confidence and sample data to find a confidence interval for the population standard deviation . Assume that the population has a normal distribution. 
|
|  |
|  |
|  |
|  |
|
|
|
The football coach randomly selected ten players and timed how long each player took to perform a certain drill. The times (in minutes) were:
10 6 8 7 5
6 5 7 8 15 Find a 95 percent confidence interval for the population standard deviation.
|
| (2.1, 5.0) |
| (2.1, 5.4) |
| (2.0, 5.0) |
| (0.7, 2.2) |
|
|
|
Find the appropriate minimum sample size. You want to be 99% confident that the sample standard deviation s is within 5% of the population standard deviation.
|
| 923 |
| 2,434 |
| 2,638 |
| 1,335 |