7. The back-to-back stem and leaf diagram shows the journey times, to the nearest minute, of the commuter services into a big city provided by the trains of two operating companies.
| Company \(A\) | Company \(B\) |
| (3) | 431 | 2 | 056689 | (6) |
| (4) | 9865 | 3 | 13479 | (5) |
| (4) | 8862 | 4 | 01358 | () |
| (6) | 975321 | 5 | 26899 | () |
| (3) | 653 | 6 | 3477 | () |
| (3) | 322 | 7 | 015 | ( ) |
Key : 4| 3 | 6 means 34 minutes for Company \(A\) and 36 minutes for Company \(B\).
- Write down the numbers needed to complete the diagram.
- Find the median and the quartiles for each company.
- On graph paper, draw box plots for the two companies. Show your scale.
- Use your plots to compare the two sets of data briefly.
- Describe the skewness of each company's distribution of times.