Answer:
35%
Explanation:
Assuming that there are no other animals in the vet other than dogs and cats, that means the total amount of animals is 21 + 39, which is 60 animals. To find the percent of cats, simply place the number of cats based on the ratio (21) over the total number of animals (60) and multiply by a 100:
21/60 = 0.35
0.35 x 100 = 35%
Hope this helps!!