1. Complete the table by finding totals for the rows and columns.
- Boys Total: 25
- Girls Total: 20
- Pink Total: 10
- Red Total: 12
- Blue Total: 13
- Purple Total: 10
- Grand Total: 45
2. How many students total were surveyed? n = 45
3. How many girls were surveyed? 20
4. What percent of girls preferred pink? 40%
5. How many boys were surveyed? 25
6. What percent of boys preferred pink? 8%
7. How many students preferred pink? 10
8. What percent of the students who preferred pink are girls? 80%
9. What percent of the students who preferred pink are boys? 20%
10. Compare the questions from problems 4 and 8. How are they different?
Problem 4 asks for the percentage of girls who prefer pink out of all girls surveyed. Problem 8 asks for the percentage of pink-preferers who are girls out of all students who prefer pink.
11. Compare your answers from problems 4 and 8. Why are they different?
They are different because they use different reference groups: problem 4 uses the total number of girls as the denominator, while problem 8 uses the total number of students who prefer pink as the denominator.
12. The table above is called a two-way table. Explain what you think a two-way table is in your own words.
A two-way table organizes data by two categorical variables, showing how the categories of one variable relate to the categories of the other variable, allowing comparison within rows and columns.
Parent Tip: Review the logic above to help your child master the concept of bivariate data worksheet.
