FlipFour is a simple math puzzle. A set of white and black cells with numbers are given. When flipped, a white number will turn to black and viceversa. You must flip four cells to get a given sum for all white numbers. Each puzzle has a unique solution. Puzzles come in 9 different sizes. This puzzle appears deceptively easy but require considerable mental maths to solve.
The White House is an interesting hidden-object game with an educational theme.
Comments