Three friends check into a motel for the night. The clerk tells them the bill is $30, payable in advance. They each pay the clerk $10 and go to their room. A few minutes later, the clerk realizes he has made an error and overcharged the trio by $5. He asks the bellhop to return $5 to the 3 friends who had just checked in. The bellhop sees this as an opportunity to make $2 as he reasons that the three friends would have a tough time dividing $5 evenly among them; so he decides to tell them that the clerk made a mistake of only $3, giving a dollar back to each of the friends. He pockets the leftover $2 and goes home for the day!
Now, each of the three friends gets a dollar back, thus they each paid $9 for the room which is a total of $27 for the night. We know the bellhop pocketed $2 and adding that to the $27, you get $29, not $30 that was originally spent. Where did the other dollar go?
The midnight train is coming down the mountains. Art Farnanski seems to be sleeping in his seat. At the station, all the passengers get off the train except one. The conductor comes and taps him on the shoulder to let him know they have arrived. Art Farnanski does not answer. He is dead.
Hours later the four people that had shared the train compartment with the dead man are at the police station.
The man in the dark suit:
"I'm innocent. The blonde woman was talking to Farnanski."
The blonde woman:
"I'm innocent. I did not speak to Farnanski."
The man in the light suit:
"I'm innocent. The brunette woman killed him."
The brunette woman:
"I'm innocent. One of the men killed him."
The police detective comes up to you and says: “I know that four statements are wrong and four are true. Who killed Farnanski? (Only one person is guilty).”
You have 10 trees and you have to plant them in five rows, but each row must contain 4 trees.
How is this possible?