A survey of 60 people was done to see which ice cream flavor they preferred, vanilla, chocolate, or strawberry. The results are as follows: 5 liked all three flavors
9 people liked chocolate and strawberry, 11 people liked vanilla and strawberry, 13 people liked vanilla and chocolate
29 people liked chocolate, 28 people liked vanilla, 28 people liked strawberry
What is the probability that a person chosen at random prefers neither of the 3 flavours?