Nudging sustainable choices can be highly effective. A social psychologist investigated whether placing a 'sad planet' sticker on a workplace hot drinks dispenser could reduce the use of disposable paper cups. Twelve office workers were recruited using a self-selected sample. In Week 1, participants recorded the number of disposable cups they used (Without sticker). In Week 2, the 'sad planet' sticker was attached to the dispenser, and the same participants recorded their weekly disposable cup usage again (With 'sad planet' sticker). The results are shown in the table below.
| Participant | Number of disposable cups used during the week | |
|---|---|---|
| Without sticker on dispenser | With 'sad planet' sticker on dispenser | |
| A | 18 | 13 |
| B | 24 | 19 |
| C | 15 | 11 |
| D | 12 | 7 |
| E | 19 | 14 |
| F | 8 | 5 |
| G | 26 | 21 |
| H | 14 | 9 |
| I | 11 | 10 |
| J | 20 | 16 |
| K | 15 | 8 |
| L | 17 | 12 |
Calculate the median and range for the number of disposable cups used in the week with the 'sad planet' sticker on the dispenser. Show your workings.
