### Efficient Cutting

Use a single sheet of A4 paper and make a cylinder having the greatest possible volume. The cylinder must be closed off by a circle at each end.

### Tin Tight

What's the most efficient proportion for a 1 litre tin of paint?

### Cola Can

An aluminium can contains 330 ml of cola. If the can's diameter is 6 cm what is the can's height?

# Tubular Stand

##### Stage: 4 Challenge Level:

A square stand designed to protect surfaces from hot pans is made from four $10 \; \text{cm}$ long pieces of cylindrical wooden dowel joined at the corners with $45$ degree mitres.

If the radius of the dowel used to make a stand is $0.5 \; \text{cm}$, what is the volume of wood used?

If I doubled the volume of wood used but did not change the radius of the dowel - what would the outside dimension of the stand be?

If, instead, I doubled the radius of the dowel but kept the same volume of wood, what would the outside dimension of the stand be then?

By looking in more detail at the effects of changing one of the variables at a time, can you describe any relationships between the volume of wood, the radius and the length of the dowel used?