Answer:
For every three kittens there is one orange kitten
Explanation:
The total number of kittens is equal to four black kittens + two orange kittens, which makes for six kittens.
So for every six kittens there are two orange kittens.
We can simplify this down further by dividing by the greatest common factor, 2.
So,
For every three kittens there is one orange kitten.