Question

In a classroom, 14 children have a dog as a pet, 11 children have cats and 3 who have both. If 24 children don't have either a cat of a dog, how many children are in the classroom.

Answer 1

Greetings from Brasil...

Using set theory to solve this question

Let

D = Dogs Set

C = Cats Set

R = Classroom Set

n(D ∪ C) = n(D) + n(C) - n(D ∩ C)

n(D ∪ C) = 14 + 11 - 3

n(D ∪ C) = 22

Then,

Total = n(D ∪ C) + 24

Total = 22 + 24

Total = 46

Answer 2

14 + 11 = 25 - 3 = 22 + 24 = 46 children