Riddle: Someone stole $20 off your desk at school. You find 4 suspects: Gina, Kelly, Peter, and Liam. You ask them all about the money: Gina: Hey, I didn't take it! Kelly: I'm pretty sure Peter took it! Peter: No way! Kelly is lying! Liam: Gina's telling the truth! One of these people is telling the truth. Who took your money?
Answer: Gina took the money. She, Kelly, and Liam are lying while Peter is telling the truth. If any of the other people had taken it, then there would be only 1 liar and 3 people telling the truth.