Consider a grid of size 4 by 4 (i.e. sixteen squares), where all squares should get a color. The colored grid should meet the following conditions:

• 4 squares should be colored blue,
• 3 squares should be colored red,
• 3 squares should be colored white,
• 3 squares should be colored green,
• 3 squares should be colored yellow, and
• no color may appear more than once in any horizontal, vertical, or diagonal line.

The question: How can the grid be colored?

A hint : Click here!

The answer: Click here!