Basics

The term *mean* is synonymous with the term *average*.

The formula provided for mean by the Mathematics Formula Sheet is not presented as a mathematical expression.

**Formulas (provided by Mathematics Formula Sheet)**

Mean is equal to the total of the values of a data set, divided by the number of elements in the data set.

** **

**Formulas (NOT provided by Mathematics Formula Sheet)
**

Sum = addition of values

Count = number of values

**
Question
**Three people weigh 170, 186, and 244 pounds, respectively. What is their mean weight?

**Answer
**200 pounds

**Answer Process**

Sum = addition of values = 170 + 186 + 244

Count = number of values = 3

Mean = = 200

Calculator Click |
What You See |
Comment |

blinker | clears screen | |

170+186+244 3 |
||

200 | Answer | |

## Mean |

**
Question
**Five people weigh 120, 150, 170, 186, and 244 pounds, respectively. What is their average weight?

**Answer
**174 pounds

**Answer Process**

Average is the same as Mean.

Sum = addition of values = 120 + 150 + 170 + 186 + 244

Count = number of values = 5

Mean = = 174

Calculator Click |
What You See |
Comment |

blinker | clears screen | |

120+150+170+186+244 3 |
||

174 | Answer | |

## Mean |

Question

The mean weight of four people is 165 pounds. What is their total weight?

**Answer
**660 pounds

**Answer Process**

Sum = 165 × 4 = 660

Calculator Click |
What You See |
Comment |

blinker | clears screen | |

165 × 4 | 165*4 | |

660 | Answer | |

## Mean |

Question

A group of people with a mean weight of 135 pounds weigh a total of 945 pounds.

How many people are in the group?

**Answer
**7

**Answer Process**

Count = = 7

Calculator Click |
What You See |
Comment |

blinker | clears screen | |

945 135 |
||

7 | Answer | |

## Mean |

Question

Three people have a mean weight of 145 pounds. One person weighs 132 pounds.

A second person weighs 186 pounds. What does the third person weigh?

**Answer
**117 pounds

**Answer Process**

Sum = Mean × Count

Sum = Mean × Count = 145 × 3 = 435

Unknown Value = Sum – Known Values

Unknown Value = 435 – 132 – 186 = 117

Calculator Click |
What You See |
Comment |

blinker | clears screen | |

145 × 3 | 145*3 | |

435 | Sum | |

435 – 132 – 186 | 435-132-186 | Unknown Value = Sum – Known Values |

117 | Answer | |

## Mean |

**
Practice – Questions
**1. Five basketball players scored 7, 12, 15, 28, and 33 points, respectively. What was their mean score?

2. Five basketball players scored 3, 6, 11, 18, and 47 points, respectively. What was their average score?

3. The mean bowling score of 8 people was 133. What was their total score?

4. A group of bowlers with a mean score of 147 had a total of score of 1617. How many bowlers were in the group?

5. Four bowlers had a mean score of 168. One bowler scored 111. A second bowler scored 133. A third bowler scored 223. What did the fourth bowler score?

**
Practice – Answers
**1. 19

2. 17

3. 1064

4. 11

5. 205