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 |
| --- | --- | --- | --- | --- | --- | --- |
| Melbourne | 15.17 (107) | North Melbourne | 6.14 (50) | MCG | 8421.0 | 10 August 1929 |
| Footscray | 11.6 (72) | Richmond | 14.15 (99) | Western Oval | 13000.0 | 10 August 1929 |
| Essendon | 15.10 (100) | Hawthorn | 13.14 (92) | Windy Hill | 11000.0 | 10 August 1929 |
| Collingwood | 13.9 (87) | Geelong | 8.12 (60) | Victoria Park | 14000.0 | 10 August 1929 |
| Carlton | 17.17 (119) | South Melbourne | 11.15 (81) | Princes Park | 20000.0 | 10 August 1929 |
| St Kilda | 21.16 (142) | Fitzroy | 10.15 (75) | Junction Oval | 14500.0 | 10 August 1929 |
Question:
What was the average crowd size when Melbourne was the home team?
Answer:
8421.0