Take a look at Mixing Paints .

Experiment with different combinations of paints A and B (and paints C and D). You could use collections of red and white counters to represent the different paints.

Different mixes produce paints that are somewhere in between the shades of paints A and B (or paints C and D).

Imagine a scale representing the shades of pink between paints A and B (or paints C and D).

How do the proportions of the two paints selected determine where the new paint will lie along that scale?

e.g.

- If equal amounts of A and B are mixed, which point along the scale will identify the ratio of red to white of the new paint?
- If the new mix contains twice as much of A than B, where will the point on the scale now be that identifies the new paint?