The average number of legs of living things is 0.01.
"If you count up all the animals in the world, the average number of legs each animal has is 0.01 legs. This is because the huge numbers of nematodes in the world, which have no legs. There are 10 to the power of 22 nematodes in the world, which means there are 100 times more nematodes than mites in the world, and 1,000 times more nematodes than insects. One nematode lives as a parasite in the human eye that can grow up to 7cm in length."
"If you count up all the animals in the world, the average number of legs each animal has is 0.01 legs. This is because the huge numbers of nematodes in the world, which have no legs. There are 10 to the power of 22 nematodes in the world, which means there are 100 times more nematodes than mites in the world, and 1,000 times more nematodes than insects. One nematode lives as a parasite in the human eye that can grow up to 7cm in length."