1. Objectives Recognise types of data Construct stem and leaf diagrams Understand grouped frequency distributions Construct cumulative frequency polygons

2. Types of Data Qualitative Quantitative Height Town of birth Height Town of birth Eye colour Age

3. Types of Data Continuous Discrete Time Volume Height Weight Cost in £’s Number of children Shoe size Number of pets

4. Stem and Leaf Diagrams 3523182520 1622273341 2737172527 2928313240 12341234 35 5 23 3 8 50 6 27 3 1 7 7 7 798 12 0 12341234 1 0 6 23 7 57 2 0 7 3 8 789 57 1 1 8 means 18

5. Stem and Leaf Diagrams 5.26.64.38.35.1 7.58.67.17.82.2 6.65.83.57.56.1 3.82.52.78.84.8

6. Grouped frequency A sample of the number of visits made to the doctor by 150 patients

7. Class 5 - 9 5959 lower class limitupper class limit 4.5 lower class boundary 9.5 upper class boundary class width 7 midpoint

8. 25 50 75 100 125 150 175 4.59.514.519.524.529.534.5