MAT103

Franklin College

Erich Prisner

Fill in numbers into the empty (red) squares such that each inner number is the sum of the four adjacent squares. Explain how you solve this and similar problems, modelling it with several equations with several variables. How do you solve a system of, say four equations with four variables? Is it possible to solve such a puzzle for any eight numbers in the white squares?

Erich Prisner, August 2003