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Find the missing values in the following table for the circles with radius (r), diameter (d) and Circumference (C).

radius (r) |
diameter (d) |
Circumference (C) |

15 cm |

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#### Solution

**Given:** radius r = 15 cm

∴ diameter d = 2 × 15 = 30 cm

Circumference C = πd units

= `22/7 xx 30`

= `660/7`

= 94.28 cm

Tabulating the results

radius (r) |
diameter (d) |
Circumference (C) |

15 cm | 30 cm |
94.28 cm |

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