A circle has a radius of 5. Using 3.14 for pi, what is its circumference?
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Correct!
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Correct answer to question 40 (Mathematics Knowledge): 31.4
Method
Circumference is 2 times pi times the radius, so 2 x 3.14 x 5 = 31.4. The choice 78.5 is the area, pi times the radius squared, a common mix-up.
Updated: November 2026
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