Eighteen (18) 2,400-square-foot dwellings may fit on one acre (43,560 square feet) of land. A dwelling is defined as a separate building with its own roof and walls; examples include houses and apartments. The number of dwellings that can fit on one acre varies depending on how many floors they have. If the buildings are three stories or less, 18 dwellings can fit on the acre. If the buildings are more than three stories, only a portion of them can be used for housing because most will be used for commercial or industrial purposes. The number of people that can fit into these dwellings depends on how crowded they are. If there is no more than one person per room then 42 people could live in these dwellings. If there are more than one person per room then some rooms would need to be combined to make space for additional people. Here are some other approximate sizes: garage doors, 60 feet by 8 feet; ballfields, 50 acres to 500 acres; basketball courts, 25 acres to 250 acres; baseball fields, 100 acres to 1,000 acres; football fields, 200 acres to 2,000 acres. A farm is defined as land used for growing crops or livestock. One acre is about 0.4 hectare or 10,080 square feet.