What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

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

Eight of us go fourth, not back, to protect our king from an attack. What are we?

Yesterday I fell from 30 feet high ladder but I don't get hurt. Why?

I ask Joseph to pick any 5 cards out of a deck with no Jokers.

He can inspect then shuffle the deck before picking any five cards. He picks out 5 cards then hands them to me (Jack can't see any of this). I look at the cards and I pick 1 card out and give it back to Joseph. I then arrange the other four cards in a special way, and give those 4 cards all face down, and in a neat pile, to Jack.

Jack looks at the 4 cards i gave him, and says out loud which card Joseph is holding (suit and number). How?

The solution uses pure logic, not sleight of hand. All Jack needs to know is the order of the cards and what is on their face, nothing more.

In a box, there is a jumble of 7 red balls, 6 blue balls, 5 green balls, and 4 yellow balls. What is the minimum number of balls, will you have to pick up so that you have at least 4 balls of the same colour?

"That Restaurant always remains crowded. This is the reason why nobody goes there".

Can you find a flaw in this statement?

A man is lying dead in a field where no one is around. His head is split open and his legs are disfigured. Near to him, there is an unopened package. No living organism can be found anywhere at the crime scene.

How did he die?

Consider this: Arnold Schwarzenegger has a big one. Michael J. Fox has a small one. Prince doesn’t have one. The Pope has one but never uses it. Bill Clinton has one and uses it all the time. What is it?

I had an infinite supply of water and 5 litres and 3 litres jars.

How would you measure exactly 4 litres in the least number of steps?