Critical Thinking Puzzles

You have a 100 coins laying flat on a table, each with a head side and a tail side. 10 of them are heads up, 90 are tails up. You can'...

Bruce is an inmate in a large prison, and like most of the other prisoners, he smokes cigarettes. During his time in the prison, Bruce ...

There are three squares in the picture and it is overlapping and forms 2 more squares. What is the greatest number of squares you can make ...

On a 12-hour digital clock, what is the smallest interval between two times that are palindromic (can be read forwards and backwards as th...

I just found a number with an interesting property: When I divide it by 2, the remainder is 1. When I divide it by 3, the remainder is 2....

There is an island with 12 islanders. All of the islanders individually weigh exactly the same amount, except for one, who either weighs mo...

There are 100 employees in a conference room in New York City. You note that 99% of them are managers. How many managers would need to leav...