SOLUTION
In this question, we are meant to expand the expression:

10% more likely
You subtract 50 from 60 to get 10
Multiply 6 by 60 then divide by two which will get you 180.
One cat has four paws, so there are 120/4=30 cats. If a "set" of cats is two uncool cats and three cool cats, there are five cats in a set, so there are 30/5=6 sets. Since each of the six sets contains three cool cats, there are 18 cool cats in the family.