Below are 40 matchsticks arranged in a square grid.

What is the fewest number of matchsticks that need to be removed so that there are no squares (of any size) remaining?

Riddle AnswerBelow are 40 matchsticks arranged in a square grid.

What is the fewest number of matchsticks that need to be removed so that there are no squares (of any size) remaining?

Riddle AnswerYou have 8 balls numbered 1, 3, 5, 7, 9, 11, 13 and 15. Select 3 balls and put them into the circles such that the sum of the numbers on them add up to 30.

Riddle AnswerA hospital has 16 isolation rooms. Each room has a patient with a different illness.

Patient in room 13 recovers and wants to say goodbye to each patient. The problem is that if he visits a patient twice, he becomes ill again.

How does he visit each patient only once and exit from room 4?

Riddle AnswerHow can you place the numbers 1 through 9 in a 3×3 grid such that every row, column, and the two diagonals all add up to 15?

Riddle Answer