Answer:
Zoe counted 20 more black kittens than white kittens.
Step-by-step explanation:
Let the white kittens be = x
Then the black kittens be = 4x
Zoe counts a total of 25 kittens.
So, we get;

=> 
Dividing both sides by 5, we get;
x = 5
White kittens are = 5
Black kittens are = 
So, the black kittens are
more than white ones.
Therefore, Zoe counted 20 more black kittens than white kittens.