A teacher recorded the number of hours spent revising and the resulting test scores for 12 students in a mathematics class. The data is presented in the table below.
| Revision Hours (hhh) | 2 | 4 | 5 | 7 | 8 | 10 | 12 | 14 | 15 | 17 | 18 | 20 |
| Test Score (sss) | 45 | 50 | 48 | 60 | 65 | 70 | 72 | 80 | 85 | 88 | 92 | 95 |
Draw a scatter graph for this information.
Give an interpretation of the correlation between the number of hours spent revising and the test scores.
The equation of the regression line for this data is s=2.84h+39.2s = 2.84h + 39.2s=2.84h+39.2.
Give an interpretation of the gradient of this regression line.
The product moment correlation coefficient (PMCC) for this data is calculated to be 0.98.
Stating your hypotheses clearly, test at the 5% significance level whether there is a positive correlation between revision hours and test scores.
Determine whether you would reach the same conclusion at the 1% significance level.
