Twenty frogs are sitting on a log floating on the surface of a river. Two of them decide to jump off into the water.

How many frogs are there on the log at this moment?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

A boy and his father are caught in a traffic accident, and the father dies. Immediately the boy is rushed to a hospital, suffering from injuries. But the attending surgeon at the hospital, upon seeing the boy, says 'I cannot operate. This boy is my son.' How is this situation explained?

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

This puzzle is for Harry Potter fans. Do you know why Tom Riddle is called Lord Voldemort?

Is the statement valid that it does not matter how much older a sibling is, eventually the younger one will be half as old as the older one?

13 decks of cards have been mixed. What is the minimum number of cards that must be taken out from the above-mixed cards to guarantee at least one 'four of a kind?

Readers with the highest levels of visual skills can find three differences between the pictures of a cow on the farm in 14 seconds. Can you? Test your visual skills now!

Those who excel at picture puzzles to find hidden objects often possess keen attention to detail, high IQ, and the ability to process visual information at lightning speed.

Solve this tricky question. You are trapped in a forest. With you, you have a gun preloaded with two bullets in it. In front of you, there is a tiger, a leopard and a jaguar.

How do you survive?