Traditional Culture Encyclopedia - Photography and portraiture - Chicken, duck and rabbit live in the same cage, with 30 heads and 72 legs. There are three times as many chickens as ducks. How many chickens, ducks and rabbits are there?

Chicken, duck and rabbit live in the same cage, with 30 heads and 72 legs. There are three times as many chickens as ducks. How many chickens, ducks and rabbits are there?

Solution:

Assuming that all animals lift their legs, there are 72-30*2= 12 legs left on the ground.

These 12 legs are rabbits, and each rabbit has two legs left, so the number of rabbits is 12/2=6.

There are 30-6=24 chickens and ducks, but the number is only three times that of ducks, so there are 24/4=6 ducks and 6*3= 18 chickens.

A: There are 18 chickens, 6 ducks and 6 rabbits.

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