The answer is 0...
It's more of a puzzle than a Question..
If you look at the Question, You might get a good grasp when it's represented in a Venn diagram, Here, you will realize there's a probability that there was a fish with a tail but no head, a head but no tail, no tail and no head... This should make any student realise that this question can't be solved just by adding up numbers
Six fish are without heads..
Buh the Question didn't say if they had tails..
Nine fish without tail, this doesn't mean they have heads..
Eight fish cut in half doesn't mean they have either a tail or a head or both.
Without heads >0
Without tail >0
Without tail or head >0
Half fish>0
You should get a better grasp if you apply the concept of Probability and Sets..
Then you will realize the total fish is 0
It cancels each other..
