What country can make you shiver?

Can you find out the missing number in the grid?

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

What jumps when it walks and sits when it stands?

How do you go from 98 to 720 using just one letter?

A bomb goes off.
Carnage.
One person, only a few feet away, survives! How can this be?

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?

No one wants to have it, but if one got it, he does not want to lose it. What is It?

When can we add 2 to 11 and get 1 as the correct answer?