Hello, Prof Paulo!

I don't trust the wording of this problem.

Besides, the solution is too simple.

The following figure is composed of 17 matches to form 6 squares *geometrically similar* to each other. Redundant . . . *all* squares are geometrically similar. Code:

----- ----- -----
| | | |
| | | |
----- ----- -----
| | | |
| | | |
----- ----- -----

There are **eight** squares which are *geometrically similar:*

. . six 1-by-1 squares,

. . two 2-by-2 squares.

Remove only 3 matches in order to get only 4 squares geometrically similar to each other. Solution:

Code:

----- -----
| | | |
| | | |
----- -----
| | | |
| | | |
----- -----

Perhaps the author meant *congruent* squares?