**Set** |
A group or collection of objects |

**Empty Set/Null Set** |
A set with no members |

**Finite Set ** |
A set in which all members can be listed |

**Infinite ** |
Set A set in which it is not possible to
name all members |

**Subset ** |
A set contained in another set |

**Natural Numbers or Counting
Numbers** |
The set of numbers beginning with one {1,
2, 3, ...} used for most counting |

**Whole Numbers** |
The set of natural numbers that includes
zero as an element {0, 1, 2, ...} |

**Integers** |
The set of whole numbers and their
opposites |

**Rational Numbers ** |
The set of integers and all fractions and
their decimal equivalents |

**Expression** |
A combination of numbers and mathematical
operations |

**Evaluate ** |
Find the numerical value of an expression |

**Absolute Value ** |
The distance a number is from zero on the
number line |

**Sum ** |
Obtained when you add 2 rational numbers |

**Difference** |
Obtained when you subtract 2 rational
numbers |

**Product ** |
Obtained when you multiply 2 rational
numbers |

**Quotient ** |
Obtained when you divide 2 rational
numbers |

**Undefined** |
Obtained when you try to divide a
rational number by zero |

**Reciprocals** |
Two numbers whose product is one |