In this matchstick arrangement you can spot nine 1×1 squares, four 2×2 squares, and one 3×3 square.
6 matchsticks can be removed so that only three squares would remain. No loose ends of the matchsticks are allowed.
What will be the total area of the three remaining squares?
One of the solutions shown in the illustration presents three squares remained, all of different areas – 1, 4, and 9 sq units respectively. Or 14 sq units in total.