# Concepts in Action: Sensorial demonstration of the difference between H1 and H2

From wikisori

## Contents

### Age

6-9.

### Materials

- Triangle fraction insets: whole, 3/3
- Constructive triangles: H1, H2 and two red T3

### Preparation

### Presentation

- Verify the congruency between the triangle whole inset and the small red equilateral triangle, by superimposing the inset on the wooden triangle.
- In the same way, we can see that this metal inset is equal to 1/6 of the grey trapezoid.
- Superimpose H2 on H1 so that the vertices of the grey hexagon coincide with the midpoints of the sides of the yellow hexagon.
- Place the 1/3 metal inset pieces over the yellow portion that remains visible.
- With this material we can cover only three places.
- However these three obtuse-angled triangles equal one small red equilateral triangle.
- Move the three thirds to the three remaining vacant spots; these three triangles correspond to the second small red equilateral triangle.

### Control Of Error

### Points Of Interest

### Purpose

### Variation

### Links

### Handouts/Attachments