10-9a Categorical Data Lesson

10-9a Categorical Data

By Regina Jackson

When the percent of each category in a table is calculated, it is called a relative frequency table.

Relative Frequency Table

A data set where the response is not a numeric value.

Example: favorite book, favorite color​

​Categorical Data

Definitions

You will need to use the percent proportion to solve some of the problems in this lesson.

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​Calculating Percents

Multiple Choice

A survey is taken to determine the most common pet that students have. What percent of students have a cat?

• 62%

• 40%

• 31%

• 29%

1.Find the total number of students.

62+84+​38+16=200

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​2. Use the percent proportion to find the percent.

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Solution

Multiple Choice

A survey is taken to determine the most common pet that students have. What percent of students have a dog?

• 42%

• 50%

• 84%

• 35%

1.Find the total number of students.

62+84+​38+16=200

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​2. Use the percent proportion to find the percent.

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Solution

Multiple Choice

A survey is taken to determine the most common pet that students have. What percent of students have a fish or a hamster?

• 17%

• 27%

• 29%

• 26%

1. Identify the percent for each category.

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​2. Add to find the combined percent of students for the two categories.

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Solution

Multiple Choice

A survey is taken to determine the most common pet that students have. Exactly 73% of students owned which two pets?

• cat & hamster

• dog & fish

• hamster & fish

• cat & dog

Use the guess and check method.

​Find two categories whose percents add up to 73%.

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Solution

​A percent bar graph displays data based on the percentage.

It is created by 1) calculating the percent of each category and 2) representing each percent with a bar on a number line.

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Percent Bar Graph

​To find the percent for each category, you will need to subtract.

Example:

Drama equals 20% because that bar begins at 30% and ends at 50%.

50-30=20​

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Percent Bar Graph

Multiple Choice

What percent of students chose badminton?

• 20%

• 50%

• 30%

• 100%

1) Find the beginning and end points for the category.

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2) Subtract to find the percent for the category.​

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Solution

Fill in the Blank

If 300 students were surveyed, then how many chose drama?

1) Find the percent for the category.

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2) Use the percent proportion to find the part for that category.​

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Solution