The following table summarizes the results of an aptitude test given to six clerks to determine the correlation between test scores (x) and sales in the first month (y) in hundreds of dollars.
| X | 25 | 42 | 33 | 54 | 29 | 36 |
| Y | 42 | 72 | 50 | 90 | 45 | 48 |
1 Find the correlation coefficient and interpret the results.
2 Calculate the regression line of y on x and predict the sales of a vendor who obtains 47 on the test.
| xi | yi | xi ·yi | xi2 | yi2 |
|---|---|---|---|---|
| 25 | 42 | 625 | 1,764 | 1,050 |
| 42 | 72 | 1,764 | 5,184 | 3,024 |
| 33 | 50 | 1,089 | 2,500 | 1,650 |
| 54 | 90 | 2,916 | 8,100 | 4,860 |
| 29 | 45 | 841 | 2,025 | 1,305 |
| 36 | 48 | 1,296 | 2,304 | 1,728 |
| 209 | 347 | 8,531 | 21,877 | 13,617 |
