There are 20 heads and 54 legs in the same cage. How many chickens and rabbits are there?

There are 20 heads and 54 legs in the same cage. How many chickens and rabbits are there?


Suppose all chickens are chickens, then rabbits have: (54-20 × 2) / (4-2) = 14 / 2 = 7 (chickens), then chickens have: 20-7 = 13 (chickens) answer: there are 13 chickens and 7 rabbits