Problem 3 of 7
Explain the circumference formula for a circle with diameter 10.
Using a hint is okay. It just tells the trainer to give you a little more review.
Hidden until you reveal it.
connect C=pi d and C=2pi r.
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Explanation must connect circumference to diameter proportionality and radius as half diameter.
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Your answer is equivalent to the expected form.
Walkthrough
Full solution stays hidden until you ask for it.
1. State that circumference is proportional to diameter by factor pi.
2. If given radius, double it to get diameter.
3. Write the equivalent circumference formula.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Using area formula pi r squared for circumference.