The mean average is a single number expressing the typical value in a set of data. It is calculated by finding the total of the set of data and dividing by how many values there are.

A set of data is collection of facts, such as numbers, words, measurements, observations or even just descriptions of things.

An outlier is a value that lies outside. It is much smaller or larger than most of the other values in a set of data.

Explain why the mean is useful and when it is not appropriate

Maths

In this unit pupils will learn how to calculate the mean of a set of data and use the mean to make comparisons between two sets of information. In the future unit pupils will calculate and compare the mean, median and mode of a set of data.

In the prior unit pupils interpreted and constructed pie charts and line graphs and used these to solve problems. They read scales and made links to fractions, angles, percentages and understanding proportional relationships. In this unit pupils will learn how to calculate the mean of a set of data and use the mean to make comparisons between two sets of information.

Mean average

An outlier is a value that lies outside. It is much _______ or ______ than most of the other values in a set of data. Select two missing words to complete the definition. 

Identify the outlying values in this set of data.

 Look at the data. Laura says we must include 0 when calculating the mean average. Lucas disagrees and says that it should not be included in this example. Who is correct? 

How long it takes for children to read 100 words.

 What size jumpers children wear from Year 1 to Year 6

Match the problem to show whether working out the mean average would be helpful or not. 

 Calculate the mean average of the spelling test scores without the outlying value.

Calculate the mean average of goals scored per match without the outlying value. The mean average is {{ }}.


Give your answer as a decimal. 45 ÷ 4 = {{ }}

If the mean average of a set of data is 7, what can the total value not be? 

 Lucas records how many times children change their books during the week in Oak Class and Willow Class. Match the correct mean average to the class. 

Here are some spelling test scores.  Laura: 12; Lucas: 10; Sofia: 8; Jun 2   Lucas says that mean average is 7 because 32 ÷ 4 = 7. Is Lucas correct?

 Calculate the mean average goal difference for the Oak hockey team.

This lesson will be removed by end of Summer Term 2025.

Explain why the mean is useful and when it is not appropriate

Lesson outcome

This lesson will be removed by end of Summer Term 2025.