Answers

2014-12-02T21:23:33+08:00
Circumference formula:
C = 2πr
C = πd
where r is the radius and d is the diameter
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d= 20m
C = πd
C = π(20m)
C = 20πm or 62.83m
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r = 4cm
C = 2πr
C = 2π(4cm)
C = 8π cm  or 25.13cm
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d = 12dm
C = πd
C = π(12dm)
C = 12π dm or 37.70 dm
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r = 6mm
C = 2πr
C = 2π(6mm)
C = 12π mm  or 37.70 mm
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d = 40 cm
C = πd
C = π(40cm)
C = 40π cm  or 125.66 cm

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