1. Homework Correction Q2 Pg 356 i.25 ii.10 iii.3

2. Pie Charts and Histograms

3. What we did last week… Created Tally Tables Created Frequency Tables Drew Bar Charts and Line plots

4. Today we will… 1.Create Pie charts from Data 1.Analyze Pie charts 1.Create Histograms from frequency Table 1.Analyze Histograms

5. Pie Charts

6. Why use a pie chart to represent data? A pie chart is a good way of displaying data when you want to show how something is shared or divided They are very useful to display categorical data

7. Pie Charts A Pie Chart is divided into sectors The Whole circle represents all the people surveyed The Angle of each sector is proportional to the frequency for that category

8. How do we draw a pie chart? You will need 1.Pencil 2.Protractor 3.Ruler

9. Step 1 Tabulate your data: Type of TransportFrequencyCalculation Train24 Coach12 Car59 Ship11 Plane14 Total120

10. Step 2 Calculate the angle needed for each category: We do this by using a simple formula

11. Complete Table Type of Transport FrequencyCalculation Train2424/120 x 360° = 72° Coach1212/120 x 360° = 36° Car5959/120 x 360° = 177° Ship1111/120 x 360° = 33° Plane1414/120 x 360° = 42° Total120360°

12. Now draw! 1.Draw a Circle using compass

13. Now Draw! 2. Measure out each angle using your protractor

14. Now draw! 3. Draw lines where appropriate and you're done!

15. Objective Check 1.Create Pie charts from Data 1.Analyze Pie charts 1.Create Histograms from frequency Table 1.Analyze Histograms

16. Analyzing Pie Charts This is the most important aspect of reading pie charts What is the use in seeing something if we cannot understand it?

17. Analyzing Pie Charts Once given certain parts of information we can work backwards to calculate something that may be missing

18. Example

19. Objective Check 1.Create Pie charts from Data 1.Analyze Pie charts 1.Create Histograms from frequency Table 1.Analyze Histograms

20. Histograms Histograms are one of the most common ways to represent data Histograms are similar to bar charts but here are some differences: There are no gaps between bars in a histogram They are used to show continuous data The data is always grouped

21. Histograms

22. Example Time (s)0 - 1010 - 2020 – 3030 - 4040 - 5050 - 60 No of Students 1281163

23. Objective Check 1.Create Pie charts from Data 1.Analyze Pie charts 1.Create Histograms from frequency Table 1.Analyze Histograms

24. Interpreting Histograms Similar to bar charts, simply read off any data needed Try for yourself Question 1 Page 361

25. Objective Check 1.Create Pie charts from Data 1.Analyze Pie charts 1.Create Histograms from frequency Table 1.Analyze Histograms

26. Homework Page 359 Q 10, 12 Page 362 Q 5

27. Next week… We will start looking at the spread of data