Homework SourseAn Math teacher is interested in examining whether his 8 AM
An Math teacher is interested in examining whether his 8 AM morning class has a different level of motivation to learn than his 2 PM afternoon class. He administers a 40-point motivational survey to a randomly drawn sample of students. The results are given to the right. Construct a 75% confidence interval of the difference in motivation scores to determine if the data supports the teacher\'s hypothesis that the time when student attends a class is related to their motivation.
| N | Mean | Median | StdDev | Min | Max | |
| Morning | 38 | 22.31 | 24 | 4.78 | 6 | 39 |
| Afternoon | 62 | 19.56 | 20 | 3.55 | 10 | 36 |
Solution
H0: mu1= mu2 (average motivation is the same irrespective of time)
Ha: mu1 not equals mu2
(Two tailed test for means)
| Sample I | II | d=Mean diff | |
| Mean | 22.31 | 19.56 | 2.75 |
| Std dev | 4.78 | 3.55 | |
| n | 38 | 62 | |
| Alpha | 0.25 | ||
| Std error | 0.8969 | ||
| Margin of error | 1.03 | ||
| 95% conf intervals | |||
| Upper | 3.781435 | ||
| Lower | 1.718565 | ||
| 75% Z alpha/2 | 1.15 |
