# Experiment-conjecture-prove - February 2008, Stage 3&4

## Problems

### Notes on a Triangle

##### Age 11 to 14 Challenge Level:

Can you describe what happens in this film?

### 9 Weights

##### Age 11 to 14 Challenge Level:

You have been given nine weights, one of which is slightly heavier than the rest. Can you work out which weight is heavier in just two weighings of the balance?

### Conway's Chequerboard Army

##### Age 11 to 14 Challenge Level:

Here is a solitaire type environment for you to experiment with. Which targets can you reach?

### Equal Equilateral Triangles

##### Age 14 to 16 Challenge Level:

Using the interactivity, can you make a regular hexagon from yellow triangles the same size as a regular hexagon made from green triangles ?

### The Square Hole

##### Age 14 to 16 Challenge Level:

If the yellow equilateral triangle is taken as the unit for area, what size is the hole ?

##### Age 14 to 18 Challenge Level:

Which of these roads will satisfy a Munchkin builder?