How many triangles do you see in this image?

Step-by-step method: counting without mistakes
Identify the “upward” triangles by their height:
Level height 1:10
Height 2 levels: 6
Height 3 levels: 3
Height 4 levels: 1
Subtotal “up”: 10 + 6 + 3 + 1 = 20.

Add the “downward-facing” triangles resulting from the nesting of the segments: 7.

Total: 20 + 7 = 27.
Memory tip: think “20 ​​on top + 7 on the bottom” and you will avoid the classic forgetfulness.

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