An old man, with four sons and three daughters, buried a safebox with valuables inside. He wanted his children to get it when he died, but neither the boys nor the girls to get it all for themselves; he desired that at least two sons and two daughters had to be involved in order to find the missing treasure.
(For example, the three girls on their own couldn't find the treasure, even if one boy helped them. The four boys and one girl couldn't find it either.)
How could he manage this?
The following steps succinctly display the procedure undertaken by the old man:
(1) The old man buries the treasure.
(2) He draws two lines on the map that intersect at the spot where the TREASURE is hidden.
(3) He calls the first line the "male line" and the second line as "female line"
(4) Each boy is given a random point in the "Male line" and each girl is given a random point in the "female line"
(5) If two boys get together, they can find one of the lines (male line, to be more precise). But unless the two girls get together it will be impossible to find the TREASURE.
Puzzle Solution
