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uncertain 2 learners

Radius substituted inconsistently

Recalls A = πr² but does not preserve the exponent during substitution.

Shared learning need

Make substitution explicit before evaluating the exponent.

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 06

1 / 2
“A = πr². I replaced r with 6 and did π × 6 × 2, giving 12π cm².”
Final answer: 12π cm²
Reconstructed reasoning

Loses the square while evaluating the area formula.

high confidence
  1. Recall

    States A = πr².

  2. Substitute

    Changes r² into 6 × 2.

Evidence in the response

  • “A = πr².”
  • “π × 6 × 2” treats the exponent as multiplication.

Alternative hypothesis

This may be exponent-notation confusion rather than substitution alone.

Teacher decision

Review this interpretation

Your judgement remains the final word for Learner 06.

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