We have two closed boxes with a label on each one. Label A on box A: "The label on box B is true and the gold is in box A" Label B on box B: "The label on box A is false and the gold is in box A" We don't know if the labels (one or both of them) are true or false. Knowing FOR SURE that the gold is in box A or in box B.
Where's the gold?
There are three houses in a straight row. One is red, one is blue, and one is white. The red house is left of the middle. The blue house is right of the middle. Where's the white house?
A mother is 21 years older than her child. In exactly 6 years from now, the mother will be exactly 5 times as old as the child.
Where's the father?
You must pay a worker exactly 1 piece of gold per day, every day for 7 days. What is the fewest number of cuts of the gold so you can pay the worker correctly?