This carpenter has a plank like the one in the illustration, which contains 81 squares the size of the smallest. That is, if the small represents an inch, the next represents 16, and the largest represents 64, making a total of 81.

Our carpenter wants to make a 9 x 9 shutter and cannot waste a millimeter of wood. He wants to divide it into the smallest possible number of pieces that fit and make a perfect square.

If you take a look at the board you can get the idea of the price of gold, silver and copper as recommended by the state of Nebraska, in ratios of 16 to 1 and 64 to 1, having the amalgam of copper or copper mixed a value of 91 to 1.

From a mathematical point of view, you learn a lot from experiencing the relationships of squares as shown in the relationship between 1, 16, 64 and 91, which is one of the fascinating characteristics of the mystery of square numbers.

**Cut the surface of the illustration into the smallest number of pieces that fit to make a square.**