You are playing a game with your friend Jack. There are digits from 1 to 9. You both will take turn erasing one digit and adding it to your score. The first one to score 15 points will win the game.

Would you want to play first or second?

PS: The sum should be exactly 15.

I look at you, you look at me, I raise my right, you raise your left. What am I?

There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

Lifeless eyes on my smiling face and watch your child's sleeping place. In their dreams they hold me tight. What am I?

How can you take 2 from 5 and leave 4?

How many cubic feet of dirt are in a hole of one foot deep, three feet long, and two feet wide?

Find out a multi-digit number that if multiplied by the number 9 or any of its multiplications products (i.e. 18, 27, 36, 45,..) will result in the multiplication factor repeated (n) number of times.

What can you catch but never throw?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?