Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Home team | Home team score | Away team | Away team score | Venue | Crowd | Date |
| --- | --- | --- | --- | --- | --- | --- |
| Footscray | 8.16 (64) | North Melbourne | 7.11 (53) | Western Oval | 15000.0 | 11 May 1929 |
| Essendon | 9.9 (63) | Richmond | 15.17 (107) | Windy Hill | 25000.0 | 11 May 1929 |
| Collingwood | 19.20 (134) | South Melbourne | 4.14 (38) | Victoria Park | 18000.0 | 11 May 1929 |
| Carlton | 13.28 (106) | Hawthorn | 9.14 (68) | Princes Park | 17000.0 | 11 May 1929 |
| St Kilda | 8.9 (57) | Geelong | 8.12 (60) | Junction Oval | 21000.0 | 11 May 1929 |
| Melbourne | 15.17 (107) | Fitzroy | 12.4 (76) | MCG | 18920.0 | 11 May 1929 |
Question:
What is the average crowd size for games with north melbourne as the away side?
Answer:
15000.0