4-2 Organizing Data Warm Up Problem of the Day Lesson Presentation Pre-Algebra

4-2 Organizing Data Warm Up Compare. Write < or >. 1. 3(6) 15 Pre-Algebra 4-2 Organizing Data Warm Up Compare. Write < or >. 1. 3(6) 15 2. 53 – 37 19 3. 27 2(14) 4. 49 – (–4) 51 > < < >

Problem of the Day If today is Wednesday, what day of the week will it be in 100 days? Friday

Learn to organize data in tables and stem-and-leaf plots.

Vocabulary stem-and-leafoplot back-to-back stem-and-leafoplot

When you graduate and start looking for a job, you may have to keep track of a lot of information. A table is one way to organize data so that you can understand the meaning and recognize any relationships.

Additional Example 1: Organizing Data in Tables Use the given data to make a table. Jack timed his bus rides to and from school. On Monday, it took 7 minutes to get to school and 9 minutes to get home. On Tuesday, it took 5 minutes and 9 minutes, respectively, and on Wednesday, it took 8 minutes and 7 minutes.

Try This Example: 1 Use the given data to make a table. Jill timed herself jogging to the park and back home. On Monday she ran to the park in 12 minutes then back home in 14 minutes, on Tuesday it took her 13 and 15 minutes, respectively, and on Wednesday, it took her 11 minutes and 13 minutes. Day To the Park Back Home Monday 12 14 Tuesday 13 15 Wednesday 11

A stem-and-leaf plot is another way to display data A stem-and-leaf plot is another way to display data. The values are grouped so that all but the last digit is the same in each category. Stem = first digits(s) 2 5 = 25 Leaf = last digit

Additional Example 2: Reading Stem-and-Leaf Plots List the data values of the stem-and-leaf plot. 1 2 5 4 0 1 1 5 2 7 9 Key: 1 2 means 12 The data values are: 12, 15, 40, 41, 41, 52, 57, and 59.

2 3 6 3 7 8 9 4 2 5 6 Key: 2 3 means 23 The data values are: Try This: Example 2 List the data values of the stem-and-leaf plot. 2 3 6 3 7 8 9 4 2 5 6 Key: 2 3 means 23 The data values are: 23, 26, 37, 38, 39, 42, 45, and 46.

Additional Example 3: Organizing data in Stem-and-Leaf Plots Use the given data to make a stem-and-leaf plot. 4 2 3 5 5 0 6 1 4 Key: 4 2 means 42 mi/h Speeds range from 42 to 64 so stems are 4 to 6.

Percent of Persons under 18 years old, year 2000 Try This: Example 3 Use the given data to make a stem-and-leaf plot. Percent of Persons under 18 years old, year 2000 Florida California Texas Arizona New York Alaska 23% 27% 28% 25% 30% 2 3 5 7 7 8 3 0 Key: 2 3 means 23% Percentage range from 23 to 30 so stems are 2 to 3.

A back-to-back stem-and-leaf plot is used to compare two sets of data A back-to-back stem-and-leaf plot is used to compare two sets of data. The stems are in the center, and the left leaves are read in reverse.

Key: | 2 | 9 means 29 representatives 8 | 1 | means 18 representatives Additional Example 4: Organizing data in Back-to-Back Stem-and-Leaf Plots Use the given data to make a back-to-back stem-and-leaf plot. 1950 2000 Key: | 2 | 9 means 29 representatives 8 | 1 | means 18 representatives 4 8 1 2 3 4 0 5 9 9 5 1 3 9

Use the given data to make a back-to-back stem-and-leaf plot. Try This: Example 4 Use the given data to make a back-to-back stem-and-leaf plot. Voting Statistics Age Voted Did not vote Millions 18 to 24 years 8 18 25 to 34 years 16 21 35 to 44 years 24 20 45 to 54 years 23 14 55 to 64 years 65 to 74 years 12 5 75 years up 10 Did not vote Voted 5 5 8 4 8 0 1 0 8 1 0 2 6 6 2 3 4 Key: | 0 | 8 means 8 million people

Lesson Quiz: Part 1 Use the given data to make a table. 1. There are three houses. The first house has 3 bedrooms, 2 bathrooms, and a full basement. The second house has 4 bedrooms, 3 bathrooms, and a partial basement. The third house has 5 bedrooms, 2.5 bathrooms, and no basement. 3 4 5 2 3 2.5 Full Partial None

Lesson Quiz: Part 2 2. List the data values in the stem-and-leaf plot. Key: 1 4 means 14 0 6 9 1 4 7 2 2 5 6, 9, 14, 17, 22, 25