Question

Three transparent glass pieces with different engravings are shown. They are overlapped one on top of the other, with the red corner exactly matching each other. What is the total number of triangles in the resultant figure? 

Hint:

For overlapping shape puzzles, always count:
1) smallest basic triangles,
2) medium triangles formed by combining,
3) largest overall triangle.

Answer 1

Step 1: Observe each engraving.
- First engraving has 2 diagonal shapes forming triangular gaps.
- Second engraving has 3 trapezoid-like shapes forming triangular gaps.
- Third engraving has 3 triangular engravings near the corner.
Step 2: Superimpose all three engravings.
When overlapped, each triangular engraving combines with the others to form multiple intersecting triangles.
Step 3: Count triangles systematically.

Careful counting of all small, medium, and large triangles (formed by overlapping lines) gives a total of 13 triangles.
Final Answer: \[ \boxed{13 \, \text{triangles}} \]