Line graphs, frequency polygons and stem and leaf diagrams
For the exam, you will need to know how to draw and interpret statistical diagrams including two way tables, line graphs, frequency polygons and stem and leaf diagrams.
Below is an example of a two-way table showing the number of boys and girls in a 6th form college:
We can find out lots of information from this table, for example:
- There are 260 girls in the college (120 + 140)
- 5/12 of the boys are in U6 (100 out of 240)
- 48% of the pupils are boys (240/500 × 100)%
- If a girl is chosen at random, the probability that she is in class L6 is 6/13 (there are 260 girls, and 120 of them are in L6, so 120/260 or 6/13)
- How many pupils are in L6?
- If a boy is chosen at random, what is the probability that he is in U6?
- There are 260 pupils in L6 (140 boys and 120 girls)
- 5/12 (100 out of 240)