A boy saw a shirt for \$97 but does not have enough cash. So he borrowed \$50 from his mom and another \$50 from his dad.

He bought the shirt, and got back \$3 as change. He gave his dad \$1 and his mom \$1 and kept the other \$1 for himself.

Now mom and dad paid \$10 each and got back \$1 each. So they paid \$49 each, totaling \$98. The boy has another \$1, adding up to \$99. Where is the missing dollar?

You have two jugs. One holds exactly 3 gallons and the other 5 gallons of water. You have unlimited supply of water. How do you fill 4 gallons of water into the five-gallon jug?

Three men go to stay at a hotel and they are charged \$30 for the room.

They split the cost with ten dollars each.

Later the manager finds out that the rate is \$25 and gives the bellboy \$5 to return to the guests. On the way to the room the bellboy reasons that \$5 would be difficult to split among three people so he pockets \$2 and gives \$1 to each person.

Now each person paid \$10 and got back \$1. So they paid \$9 each, totalling \$27. The bellboy has another \$2, adding up to \$29. Where is the missing dollar?

A man lives on the twelfth floor of an apartment building. Every morning he takes the elevator down to the lobby and leaves the building. In the evening, he gets into the elevator, and, if there is someone else in the elevator or if it was raining that day, he goes back to his floor directly. Otherwise, he goes to the tenth floor and walks up two flights of stairs to his apartment that is on the twelfth floor. Why?