Two friends were stuck in a cottage. They had nothing to do and thus they started playing cards. Suddenly the power went off and Friend 1 inverted the position of 15 cards in the normal deck of 52 cards and shuffled it. Now he asked Friend 2 to divide the cards into two piles (need not be equal) with equal number of cards facing up. The room was quite dark and Friend 2 could not see the cards. He thinks for a while and then divides the cards in two piles.

On checking, the count of cards facing up is same in both the piles. How could Friend 2 have done it ?

How can you take 2 from 5 and leave 4?

There is a box full of marbles,
all but two are blue,
all but two are green,
and all but two are red.

How many marbles are in the box?

Which digit occurred maximum times between the number 1 and 1000?

There was a strange boy who was born before his father. How can this be possible?

During which month do people sleep the least?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

I welcome the day with a show of light, I stealthily came here in the night. I bathe the earthy stuff at dawn, But by noon, alas! I'm gone.

What is the end of everything?

By including only four matchsticks in below picture, you have to make "Four Triangles And Two Squares"