Teaching mathematics
Teaching mathematics

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Teaching mathematics

3.1 Using simple ratios to make comparisons

First, look at Figures 20–22 and then do the activity based on them.

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Figure 20 Using Cuisenaire rods to represent ratios
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Figure 21 Using Cuisenaire rods to compare the ratio of lengths
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Figure 22 Using multilink cubes to represent ratios

Activity 18 Writing ratios

Timing: Allow 5 minutes

Write the ratios for each of the images shown above in the simplest form.

  • a.What is the ratio of red rods to yellow rods?
  • b.What is the ratio of the lengths of the green and white rods?
  • c.What is the ratio of orange to white cubes?


  • a.10:4 which simplifies to 5:2.
  • b.3:1.
  • c.12:8 which simplifies to 3:2.

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