1.6 Two-way tables
When data falls into more than one category or a learner is interested in investigating more than one variable, data cannot be organised easily in a frequency table.
Two-way tables are a way of sorting data so that the frequency of each category can be seen quickly and easily.
For example, a learner has asked 20 people about whether they like football and whether they like rugby. The results can be seen in the two-way table below.
From the table, it can be seen that there were 9 people who liked both rugby and football and 4 people who liked neither sport. It can also be seen that there were people who liked rugby but not football, and 5 people who liked football but not rugby.
|Like football||Do not like football|
|Do not like rugby||5||4|
Activity 5 Interpreting a two-way table
Use the information presented in the two-way table below to answer the following questions.
- How many right-handed students are there in the class?
- How many students are there in the class in total?
|Do not like art||1||10|
- There are 22 right-handed students in the class as this is the sum of the ‘right-handed’ column.
- There are 25 students in total. This is the sum of the ‘left-handed’ and ‘right-handed’ columns.