Curriculum extra Unit 8 Focus on Maths: Statistics 1 Read Sandra's notes about a survey she did at school. Then complete the bar chart. 3 With your partner, choose a question for a short survey. Decide on the size of your sample. One student should ask the question and the other should make a note of the answers. Use one of these questions or think of your own: Survey notes school population: 640 students sample: 80 students horizontal axis: number of hours of TV per week vertical axis: number of students How many hours do you spend … browsing the internet every day? playing computer games every week? Responses 30 hours: 5 students 25 hours: 8 students 20 hours: 16 students 15 hours: 24 students 10 hours: 19 students 5 hours: 8 students How often do you … wash up every week? go shopping every month? 4 Analyse people’s responses and produce a bar chart. Use exercise 1 to help you to organize your information. 5 Present your bar chart to the class. Use the instructions and the phrases to help you. Explain what the question was. Say how big your sample was. Say how big the total population was. Point out any peaks and troughs on your chart. Say what the mode and mean numbers on your chart are. Finish with a conclusion. 2 Work with a partner. Compare your bar charts and answer the questions about the survey together. 1 What question did Sandra ask the students? 2 Did everyone in the school take part in the survey? 3 What is the mode, or most popular answer? 4 Is there a trough, or least popular answer? What is it? 5 Use a calculator to find the mean, or average, number of hours that students spend doing the activity. 6 Imagine you are at Sandra’s school. Add your answers to the survey to her notes, and the bar chart. 3 We wanted to find out We talked to a sample of … students On our chart, In conclusion, how long students spend browsing the internet / playing computer games. how often students wash up / go shopping. out of a total population of … students. there is a peak / trough here. the mode / mean is … . a lot / only a few / most of us …