The reaction time of five students was tested using a computer-based visual stimulus test. The students first completed the test in a quiet room, and then completed it while listening to loud music. Table 1 shows their reaction times.
| Student | Reaction time in silence (seconds) | Reaction time with music (seconds) | Difference (seconds) |
|---|---|---|---|
| 1 | 0.220 | 0.245 | +0.025 |
| 2 | 0.198 | 0.212 | +0.014 |
| 3 | 0.240 | 0.262 | +0.022 |
| 4 | 0.215 | 0.225 | +0.010 |
| 5 | 0.205 | 0.224 | +0.019 |
Calculate the mean difference in reaction time. Give your answer in milliseconds.
