Study Figure 6b, which shows data about volcanic ashfall depth over 6 days during an eruption event.
Figure 6b
| Day | Ashfall depth (mm) |
|---|---|
| 1 | 15 |
| 2 | 28 |
| 3 | 42 |
| 4 | 19 |
| 5 | 11 |
| 6 | 6 |
Calculate the mean daily ashfall depth.
Give your answer to one decimal place.
You must show all your workings in the space below.
