5 toucans
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Firstly, determine the existing ratio of toucans to parrots in the initial zoo.
We achieve this by dividing the number of toucans by the number of parrots:
- 15 toucans / 60 parrots =
- 1 / 4
Secondly, we need to maintain this same ratio in the smaller zoo that currently has 20 parrots.
To figure out how many toucans they need to have the same ratio, we divide the number of parrots in the smaller zoo by 4.
Therefore the smaller zoo should have 5 toucans for their 20 parrots.