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Mixing More Paints

Stage: 3 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

This problem follows on from Mixing Paints .

It may be useful to provide students with red and white counters so that they can simulate the effect of mixing the paints.

A possible start to using this problem in a classroom could involve asking students to suggest possible combinations of paints A and B (or C and D) and their suggestions could be written up for all to see.

Possible follow up questions:
  • What is the ratio of red to white paint in these mixes?
  • Can any of these ratios be simplified?
  • Imagine a scale representing the shades of pink between paints A and B (or paints C and D).
    • Where do your mixes lie along the scale?
    • How can I produce a paint that lies exactly in between these two points?
    • How can I produce a paint that lies one quarter of the way along the scale?