There is an abandoned aquarium in an empty house. The aquarium has three large fish and three small fish. But after a week, one large fish and two small fish die.

How many remain in the aquarium?

How could the 22nd and the 24th U.S. Presidents have the same parents, but not be brothers?

What is the longest unscientific English word that uses every letter in the word exactly twice? For example, noon has two Ns and two Os, but it’s not nearly long enough.

I’m in an elevator with two other people. When it reaches the first floor, one person gets out and six get in. When it reaches the second floor, three people get out and twelve get in. At the third floor, five leave and nine enter. It rises to the fourth floor, one person gets on and the doors close. Suddenly, the elevator cable snaps and the car smashes to the ground. No one survives the fall, yet I’m alive and know exactly how many people go on and off the elevator at every floor. How is this possible?