Can start by finding out all the percentages by what is given in the question and the lines. The pie is divided into half by one line and horses and rabbits are same size.

Then, in order to find out how many more chickens than cows, we take the percentage of chickens minus percentage of cows. Since we know 13 percent is equal to 52, we can use a simple division and multiplication to find out the number of animals that 18 percent contain, which is the difference. Hope it helps!