**Teacher :** |
**What about the volume of a cylinder?
Stu1 was on the right track.** |

**Teacher :** |
**Stu1, tell me what you had for
the volume of a cylinder. Not the number but the formula.** |

**Student1:** |
**r times r times pi...** |

**Teacher :** |
**Okay, he was on the way, he said
radius times radius times pi,** |

**Teacher :** |
**or radius squared times pi. But
Holly, why is that not exactly correct?** |

**Student2:** |
**Because it's radius times radius
times pi times height** |

**Teacher :** |
**Yeah, because if you look up here,
radius times radius times pi radius squared gives us just** |

**Teacher :** |
**the base of that cylinder, right?
The area of the base.** |

**Teacher :** |
** I want to find the volume, so
we have to multiply it by height. ** |

**Teacher :** |
**I want to find the volume, so we
have to multiply it by height.** |