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attention 3 learners

Area scales linearly with radius

Treats radius and area as directly proportional, missing the squared relationship.

Shared learning need

Connect the visual growth of a circle to the r² term.

Assessment question
A circle has a radius of 3 cm. What happens to its area when the radius is doubled? Explain your reasoning.
Selected response

Learner 01

1 / 3
“The area doubles because the radius doubles. It was 9π, so it becomes 18π cm².”
Final answer: 18π cm²
Reconstructed reasoning

Applies a ×2 scale factor directly to area.

high confidence
  1. Recall

    Identifies the original area as 9π.

  2. Scale

    Transfers the radius scale factor directly to area.

  3. Conclude

    Reports 18π cm².

Evidence in the response

  • “The area doubles because the radius doubles.”
  • Correctly establishes the original area as 9π.

Alternative hypothesis

The learner may be using an intuitive visual estimate rather than a stable proportional rule.

Teacher decision

Review this interpretation

Your judgement remains the final word for Learner 01.

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