GATE General Aptitude: GATE 2019 General Aptitude (GA) Set-2 questions with solutions

Q1. Under a certain legal system, prisoners are allowed to make one statement. If their statement turns out to be true then they are hanged. If the statement turns out to be false then they are shot. One prisoner made a statement and the judge had no option but to set him free. Which one of the following could be that statement?

1. I did not commit the crime
2. I committed the crime
3. I will be shot
4. You committed the crime

Answer: I will be shot

The statement "I will be shot" creates a paradox; if the statement is true, the prisoner should be shot, which would make the statement false. Conversely, if the statement is false, the prisoner cannot be shot, meaning the statement must be true. This contradiction leaves the judge with no choice but to set the prisoner free.