# Lesson Thirteen

In this lesson you will learn to create a program that calculates information using your data. We are going to calculate averages, the high point and the low point of your data.

## Averages

An “average” is maths term that means a central or middle value for a set of numbers. You get an average by adding up all of the numbers in a group, and then dividing the total (or sum) by how many numbers are in that group. For example:

Group of numbers: 5, 7, 10, 4, 2, 2

Add together to find sum total of the group: 5 + 7 + 10 + 4 + 2 + 2 = 30

Divide sum total by the number of numbers in the group: 30 ÷ 6 = 5**The average of this group is 5**

Average numbers are important because they give us a general idea of what is happening in a set of data. For instance, if you eat **3 eggs** for breakfast on Saturday and **5 eggs** for breakfast on Sunday, the average is **4 eggs** per day. Averages help us make predictions and decisions – now you can predict that you’ll eat an average of 4 eggs for breakfast, so you need to have 8 eggs in the fridge each weekend (and maybe that you’re eating too many eggs!).

## Working with your data

Your Electric Garden will have collected a lot of data about your garden. You can see and create graphs that contain this data when you log in, but you can also download the data onto your computers and use it to calculate useful information.

Download data from your Electric Garden and follow these instructions** **use Scratch to calculate the averages for your data. How does your data compare to the average monthly temperatures of your nearest big town or city?

## Highs and Lows

It can be useful to work out the highest and lowest numbers in a data set. As humans, it is easy for us to look at a group of numbers and find the highest. Try it here by clicking on the coloured boxes and writing the highest number in the space!

Follow these instructions to write a Scratch program to calculate the highest and lowest numbers in your data set. How does your data compare to historical record temperatures?

## Making better decisions

Working out information such as highs, lows and averages allows you to make better decisions based on evidence. As a group, talk about what decisions you might make differently from the information you have found out. For example, if the average soil moisture is out of the optimal or ‘Goldilocks’ range, you might decide to water the garden more often.