1. Course 1 6-9 Stem-and-Leaf Plots 6-9 Stem-and-Leaf Plots Course 1 Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day

2. Course 1 6-9 Stem-and-Leaf Plots Warm Up A set of data ranges from 12 to 86. What intervals would you use to display this data in a histogram with four intervals? Possible answer: 10–29, 30–49, 50–69, 70–89

3. Course 1 6-9 Stem-and-Leaf Plots Problem of the Day What is the least number that can be divided evenly by each of the numbers 1 through 12? 27,720

4. Course 1 6-9 Stem-and-Leaf Plots Learn to make and analyze stem-and-leaf plots.

5. Course 1 6-9 Stem-and-Leaf Plots Vocabulary stem-and-leaf plot

6. Course 1 6-9 Stem-and-Leaf Plots A stem-and-leaf plot shows data arranged by place value. You can use a stem-and-leaf plot when you want to display data in an organized way that allows you to see each value.

7. Course 1 6-9 Stem-and-Leaf Plots Additional Example 1: Creating Stem-and-Leaf Plots Use the data in the table to make a stem-and- leaf plot. Test Scores 7586839194 8884997986 Step 1: Group the data by tens digits. Step 2: Order the data from least to greatest. 75 79 83 84 86 86 88 91 94 99

8. Course 1 6-9 Stem-and-Leaf Plots To write 42 in a stem-and-leaf plot, write each digit in a separate column. 4 2 Helpful Hint Stem Leaf

9. Course 1 6-9 Stem-and-Leaf Plots Additional Example 1 Continued Step 3: List the tens digits of the data in order from least to greatest. Write these in the “stems” column. Step 4: For each tens digit, record the ones digits of each data value in order from least to greatest. Write these in the “leaves” column. Step 5: Title the graph and add a key. Stems Test Scores Key: 7 5 means 75 Leaves 7 8 9 5 9 3 4 6 6 8 1 4 9 75 79 83 84 86 86 88 91 94 99

10. Course 1 6-9 Stem-and-Leaf Plots Check It Out: Example 1 Use the data in the table to make a stem-and- leaf plot. Test Scores 7288647961 8483767467 Step 1: Group the data by tens digits. Step 2: Order the data from least to greatest. 61 64 67 72 74 76 79 83 84 88

11. Course 1 6-9 Stem-and-Leaf Plots Check It Out: Example 1 Continued Step 3: List the tens digits of the data in order from least to greatest. Write these in the “stems” column. Step 4: For each tens digit, record the ones digits of each data value in order from least to greatest. Write these in the “leaves” column. Step 5: Title the graph and add a key. Stems Test Scores Key: 6 1 means 61 Leaves 6 7 8 1 4 7 2 4 6 9 3 4 8 61 64 67 72 74 76 79 83 84 88

12. Course 1 6-9 Stem-and-Leaf Plots Additional Example 2: Reading Stem-and-Leaf Plots Find the least value, greatest value, mean, median, mode, and range of the data. StemsLeaves 4 5 6 0 0 1 5 7 1 1 2 4 3 3 3 5 9 9 7 8 9 0 4 4 3 6 7 1 4 The least stem and least leaf give the least value, 40. The greatest stem and greatest leaf give the greatest value, 94. Use the data values to find the mean (40 + … + 94) ÷ 23 = 64. Key: 4 0 means 40

13. Course 1 6-9 Stem-and-Leaf Plots Additional Example 2 Continued The median is the middle value in the table, 63. To find the mode, look for the number that occurs most often in a row of leaves. Then identify its stem. The mode is 63. The range is the difference between the greatest and the least value. 94 – 40 = 54. StemsLeaves 4 5 6 0 0 1 5 7 1 1 2 4 3 3 3 5 9 9 7 8 9 0 4 4 3 6 7 1 4 Key: 4 0 means 40

14. Course 1 6-9 Stem-and-Leaf Plots Check It Out: Example 2 Find the least value, greatest value, mean, median, mode, and range of the data. StemsLeaves 3 4 5 0 2 5 6 8 1 1 3 4 4 5 6 9 9 9 6 7 8 1 2 4 5 6 9 1 5 The least stem and least leaf give the least value, 30. The greatest stem and greatest leaf give the greatest value, 85. Use the data values to find the mean (30 + … + 85) ÷ 23 = 55. Key: 3 0 means 30

15. Course 1 6-9 Stem-and-Leaf Plots Check It Out: Example 2 Continued The median is the middle value in the table, 56. To find the mode, look for the number that occurs most often in a row of leaves. Then identify its stem. The mode is 59. The range is the difference between the greatest and the least value. 85 – 30 = 55. StemsLeaves 3 4 5 0 2 5 6 8 1 1 3 4 4 5 6 9 9 9 6 7 8 1 2 4 5 6 9 1 5 Key: 3 0 means 30

16. Course 1 6-9 Stem-and-Leaf Plots Lesson Quiz: Part I 1. Make a stem-and-leaf plot of the data. 42 36 40 31 29 49 21 28 52 27 22 35 30 46 34 34 21 2 7 8 9 3 0 1 4 4 5 6 40 2 6 9 5 2 StemsLeaves Key: 3 | 0 means 30

17. Course 1 6-9 Stem-and-Leaf Plots Lesson Quiz: Part II Find each value using the stem-and-leaf plot. 2. What is the least value? 3. What is the mean? 4. What is the median? 5. What is the mode? 34.75 21 34