Computing Conditional Relative Frequencies

This lesson covers how to compute conditional relative frequencies by identifying parts and totals. It begins with a review of calculating percentages using a set of colored squares. The lesson then explains frequency tables, focusing on two-way tables that relate happiness levels to income. It demonstrates calculating relative frequencies by setting up fractions and converting them to percentages. The lesson concludes with conditional relative frequencies, emphasizing conditions like income level, and provides examples to illustrate these concepts.

What is the first step in calculating the percentage of orange squares?

• Multiply the number of orange squares by 100.

• Set up a fraction with the number of orange squares as the numerator.

• Divide the number of green squares by the total number of squares.

• Count the total number of squares.

In a two-way frequency table, what does the number 21 represent in the context of happiness and income?

• The total number of people surveyed.

• The number of people with average income who are very happy.

• The number of people with above average income who are not too happy.

• The number of people with below average income who are pretty happy.

How do you calculate the percentage of people who are very happy from a survey?

• Subtract the number of unhappy people from the total.

• Count the number of very happy people and multiply by 10.

• Divide the number of very happy people by the total number of people surveyed and multiply by 100.

• Add the number of very happy and pretty happy people.

What is the key difference between relative frequency and conditional relative frequency?

• Relative frequency is always higher than conditional relative frequency.

• Conditional relative frequency does not use a total.

• Conditional relative frequency considers a specific condition or subset.

• Relative frequency only applies to two-way tables.

In the example of conditional relative frequency, what percentage of people with above average income were very happy?

• 13%

• 30%

• 38%

• 25%