1 A teacher believes that the calculator paper in a GCSE Mathematics examination was easier than the non-calculator paper. The marks of a random sample of ten students are shown in the table.
| Student | A | B | C | D | E | F | G | H | I | J |
| Mark on paper 1 (non-calculator) | 66 | 79 | 58 | 87 | 67 | 55 | 75 | 62 | 50 | 84 |
| Mark on paper 2 (calculator) | 57 | 84 | 70 | 90 | 75 | 42 | 82 | 72 | 65 | 82 |
- Use a Wilcoxon signed-rank test, at the \(5 \%\) significance level, to test the teacher's belief.
- State the assumption necessary for this test to be applied.