This classic riddle says: A farmer has 4 haystacks in one field and 5 haystacks in another. He combines them all. How many haystacks does he have now?
The answer is: one haystack.
At first, the numbers make you want to add 4 + 5 and answer 9. But the important part is that the farmer combines them all.
If all nine separate piles of hay are physically joined together, they become one large haystack rather than nine individual ones.
The arithmetic is not the real challenge here. The riddle tests whether you focus on what happens to the haystacks after they are combined. Before combining, there are nine. After combining them into a single pile, there is just one haystack.
