Introduction

Understand the concept of mean average and learn how to find the mean of a set of data. Use the mean to compare sets of data and learn when it is appropriate to use the mean.

Teaching points

• Teaching point 1: The mean is the size of each part when a quantity is
  shared equally.
   
• Teaching point 2: The mean is defined as the sum of all the numbers in a set of data divided by the number of numbers/values that make up the set of data. If we know the mean of a set of data and the number of numbers/values in that set, we can calculate the total of the set. The mean of a set changes if the total value of the set changes or if the number of numbers/values in the set changes.
   
• Teaching point 3: The mean can be used to compare data.
   
• Teaching point 4: The mean is not always an appropriate representation of a set
  of data.