Homework Sourse1 From the following data what distribution should be used t
1. From the following data, what distribution should be used to calculate a 95% confidence interval for the population mean from the sample data.
T-distribution
z-distribution
chi-square distribution
f-distribution
2. From the dataset create a 95% confidence interval for the population mean from the sample data.
Determine the LCL for the interval.
3. From the dataset, create a 95% confidence interval for the population mean from the sample data.
Determine the UCL for the interval.
| 45.0299258 |
| 50.41998976 |
| 49.49846336 |
| 50.98907515 |
| 47.65872747 |
| 53.88862975 |
| 52.60615673 |
| 51.41441854 |
| 53.42351507 |
| 50.28630041 |
| 50.15869739 |
| 46.02637911 |
| 43.71514935 |
| 50.82111513 |
| 54.76679418 |
| 55.51006599 |
| 48.11577584 |
| 38.85869684 |
Solution
1) Since we can find the mean and sample standard deviation,,, So, T-distribution should be used.
Hence the ans is option -A.
2) Mean = 49.62155
sample std dev = 4.211178
T0.95,17 = 2.110
so, LCL for the interval = Mean - T0.95,17 * (sample std dev / sqrt(18))
= 49.62155 - 2.110 * ( 4.211178 / srt(18)) = 47.5272 (ans)
3) UCL for the interval = Mean + T0.95,17 * (sample std dev / sqrt(18))
= 49.62155 + 2.110 * ( 4.211178 / srt(18)) = 51.7159 (ans)
