# TSI Math: Using Circumference to Calculate a Circle's Area

A circle has an area of 225π square units. What is its circumference?

Geometry and Measurement | Measurement (Linear, Area, Three-Dimensional) |

Mathematics and Statistics Assessment | Measurement (Linear, Area, Three-Dimensional) |

Product Type | TSI |

TSI | Mathematics and Statistics Assessment TSI Math TSI Mathematics |

TSI Math | Geometry and Measurement |

TSI Mathematics | Geometry and Measurement |

Test Prep | TSI |

### Transcript

is pi times are squared so we're given pi r

squared is to twenty five pie and weaken solve a

little bit so cross out pie on both sides and

we have our squared to twenty five So square root

of two twenty five is what yes fifteen Well the

circumference of a circle is its perimeter The formulas to

pie are there since we know that our is fifteen

we're good to go It's two pi r is two

pi times fifteen or thirty pie that's the circumference of

the circle thirty pie units and the answer is d 00:00:51.635 --> [endTime] there were shmoop circular lately