### Floored

A floor is covered by a tessellation of equilateral triangles, each having three equal arcs inside it. What proportion of the area of the tessellation is shaded?

### Pie Cuts

Investigate the different ways of cutting a perfectly circular pie into equal pieces using exactly 3 cuts. The cuts have to be along chords of the circle (which might be diameters).

### Getting an Angle

How can you make an angle of 60 degrees by folding a sheet of paper twice?

# Angle A

##### Stage: 3 Challenge Level:

from Del Hawley

The three corners of a triangle are sitting on a circle. The angles are called Angle A, Angle B and Angle C. The dot in the middle of the circle shows the centre. The counter is measuring the size of Angle A in degrees.

What is the smallest Angle A can be?
What is the largest Angle A can be?
What else do you notice about Angle A as you move the corners of the triangle around the circle?

This problem is interactive, which means that you can move parts of the picture around and see what happens. Just click and drag the corners of the triangle.