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The "Double-R-7" Ranch has a new owner. The 20 animals, all hummingbirds and mice, are dismayed, as they have heard that he is both foolish and inexperienced. Not being quite sure what he was looking for, however, he checked on the health of his animals by inspecting all their feet. There were 64 feet in all. How many hummingbirds and how many mice are on this ranch?
Please help immediately I'm so confused!!! :(