# Number Operations - October 2005, Stage 2&3

## Problems

### Fractional Wall

##### Stage: 2 Challenge Level:

Using the picture of the fraction wall, can you find equivalent fractions?

##### Stage: 2 Challenge Level:

Use the fraction wall to compare the size of these fractions - you'll be amazed how it helps!

### Combining Cuisenaire

##### Stage: 2 Challenge Level:

Can you find all the different ways of lining up these Cuisenaire rods?

### Fault-free Rectangles

##### Stage: 2 Challenge Level:

Find out what a "fault-free" rectangle is and try to make some of your own.

### Rod Fractions

##### Stage: 3 Challenge Level:

Pick two rods of different colours. Given an unlimited supply of rods of each of the two colours, how can we work out what fraction the shorter rod is of the longer one?

### Colour Building

##### Stage: 3 Challenge Level:

Using only the red and white rods, how many different ways are there to make up the other colours of rod?

### Harmonic Triangle

##### Stage: 3 Challenge Level:

Can you see how to build a harmonic triangle? Can you work out the next two rows?