mysteryman on 19 February 2015
Correct.
It is now time to prepare the king hIs breakfast. However the King is very picky, and failure to cook his egg as required will result in death.
His majesty's egg must be boiled for exactly 9 minutes. You have no other means of measuring time except for a 7-minute and 4-minute hourglass.
What is the minimum amount of time required to prepare a 9-minute-boiled egg using just these two hourglasses?
