When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?
Speaking of rivers, a man calls his dog from the opposite side of the river. The dog crosses the river without getting wet, and without using a bridge or boat. How?
A Japanese ship was en route to a mission on foreign seas. The captain of the ship felt tired and thought of taking a bath. He went for taking the shower and removed his diamond ring and Rolex and kept them on the table. When he returned after taking the bath, he found that the ring and watch were stolen.
He called the five members of the crew whom he suspected and asked them what they were doing for the last 15 minutes.
The Italian cook (with a butcher knife in hand): I was in the fridge room getting meat for cooking.
The British Engineer (with a high beam torch in hand): I was working on a generator engine.
The Pakistani seaman: I was on the mast correcting the flag which was upside down by mistake.
The Indian Radio officer: I was trying to make a contact with the company to inform them about our position.
The American navigation officer: I am on night watch, so I was sleeping in my cabin.
Upon listening to them, the captain caught the lying member. Who do you think stole the valuables?
Here is what you have to do. You have to throw a ball as hard as you can but it must return back to you even if it does not bounce at anything. Also, you have nothing attached to the ball. There is no one on the other end to catch that ball and throw it back at you.
The King of a distant land had heard that Birbal was one of the wisest men in the East and so desired to meet Birbal. He sent Birbal an invitation to visit his country.
In due course, Birbal arrived in the distant kingdom. When he entered the palace he was flabbergasted to find not one but six kings seated there. All looked alike. All were dressed in kingly robes. Who was the real king?
The very next moment he got his answer. Confidently, he approached the king and bowed to him.
In 2011, people playing Foldit, an online puzzle game about protein folding, resolved the structure of an enzyme that causes an Aids-like disease in monkeys. Researchers had been working on the problem for 13 years. The gamers solved it in three weeks.
