Answer :
So, if 30 housholds have a cat 30/2 is 15.
15 housholds have a cat and a dog
30-15= 15 housholds have only cats
40-15=25 housholds only have dogs
25+15+15=55
60 housholds in total, so what is 60-55? <-- This will be your answer.
15 housholds have a cat and a dog
30-15= 15 housholds have only cats
40-15=25 housholds only have dogs
25+15+15=55
60 housholds in total, so what is 60-55? <-- This will be your answer.