AI generatedRatio, proportion and rates of changeKS3 / GCSE

Solving an equality of ratios

Equal ratios describe the same multiplicative relationship.

  • Equal ratios describe the same multiplicative relationship.
  • Find the scale factor using the two matching known quantities.
  • Apply that scale factor to the missing quantity, then check both ratios simplify to the same result.

Example 1

Find .

Compare the matching second parts.Scale the first part by the same factor.

Example 2

Find .

Compare the matching second parts.Scale the first part by the same factor.

Remember
Use the worked steps to check your method, not just the final answer.

Your turn

Question 1

Find .

Check answer
Compare the matching second parts.Scale the first part by the same factor.
Question 2

Find .

Check answer
Compare the matching second parts.Scale the first part by the same factor.
Question 3

Find .

Check answer
Compare the matching second parts.Scale the first part by the same factor.
Question 4

Find .

Check answer
Compare the matching second parts.Scale the first part by the same factor.
Question 5

Find .

Check answer
Compare the matching second parts.Scale the first part by the same factor.
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