# Describing Data

When we describe data at GCSE, we are basically after two things: the location and the spread.

The location of data is given as the average. More often than not, the average we want to use is the median because it is not as vulnerable to outliers (which are data points that do not follow the normal pattern).

The spread is how widely the data is distributed. This is measured in one of two ways. The range is simply the maximum value of data take the minimum value of data. This is affected by outliers. A better measure would be the inter-quartile range. This is the range of the middle band of data between the upper and lower quartiles.

## Averages Examination

Examination questions involving using averages to find the answer.

## Video on working out the different averages

Looking at how to calculate the arithmetic mean, median and the modal averages of a small set of data.

Work out different averages and the spreadsheet will tell you if you have the answers correct or not.

## Spreadsheet on averages and range

Work out different averages and the range and the spreadsheet will tell you if you have the answers correct or not.

## Self marking maximum and minimum spreadsheet

Work out different averages and the spreadsheet will tell you if you have the answers correct or not.

## Video on interpreting graphs

KS2 exercises on interpreting graphs and bar charts.

## Video on frequency trees

Video on completing frequency trees.

## Answering questions of numbers on a grid

Answer questions about numbers on a number grid including things like averages, maximum and minimum etc.

## Interpreting a pie chart

Answer questions comparing one pie chart to another.

## Frequency diagrams

Frequency Tables and Averages.