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.

Can you count the number of blocks in the picture below?

Below, you will find the mathematical proof that 10 equals 9.99999?. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10

Who can jump higher than a Mountain?

The day before yesterday I was 25 and the next year I will be 28. This is true only one day in a year. What day is my birthday?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

Count the squares in the matchstick puzzle below?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

Which city is three-fifths chick two third cat and 50% goat?