# Measuring road signs

This task is about working out the circumference, circular and square area of a road sign.

The figure below shows a circular 50 km/h sign, punched out of a square sheet of metal of sides 60 cm. (Use = 3.14 approx.) |

a) |
What is the circumference of the outer circle? __________ cm |

b) |
What is the area of the circular sign? __________ cm^{2
} |

c) |
What is the total area of sheet metal wasted in the four corners, after the sign is punched out?
__________ cm |

d) |
The shaded ring has an inner diameter of 40 cm, and an outer diameter of 60 cm.
What is its area? __________ cm |