Question

a veterinarian survey 26 of his patrons.e discovers that 14 have dogs ,10have cats ,and 5 have fish .our have dogs and cats ,3 have have dogs and fish ,and one has a cat and fish .if no one has all three kinds of pets ,how many patrons have none of these pets?

Answer 1

14 - 4 - 3 = 7 have only dog
10 - 4 - 1 = 5 have only cat
5 - 3 - 1 = 1 has only fish
so 13 have only one animal
3+4+1 = 8 have two animals
total with animals = 13 + 8 = 21 have animals
so
26 - 21 = 5 have no animals at all