To find the fraction of animals that were neither cats nor dogs in the costume contest, you first need to determine how many animals were either cats or dogs and then subtract that from the total number of animals.
Let's assume there were a total of "x" animals in the contest.
If "y" of them were dogs and "z" were cats, you know that:
"y" animals were dogs.
"z" animals were cats.
Now, to find the fraction that were neither cats nor dogs, you subtract the total number of cats and dogs from the total number of animals:
Total number of animals - (Number of dogs + Number of cats) = x - (y + z)
So, the fraction of animals that were neither cats nor dogs is:
(x - y - z) / x
This fraction represents the animals that were something other than cats or dogs.