Answer: 30%
Explanation:
There are 12 families that own a bulldog and there are total of 40 families that own a dog. Percentage of dogs owners with a bull dog can be written as:
Number of bulldog owners/Total number of dog numbers × 100
= 12/40 × 100
= 3/10 × 100
= 30%
The percentage of bulldog owners is 30%.