Question 1: Explain the purpose of the Key in a stem and leaf diagram. Why is it important?

Answer: The Key explains what the stems and leaves represent, helping interpret the data correctly.

Question 2: Create a Key for the following data set: 12, 15, 13, 18, 11, 17, 14.

Answer: Key: 1 | 2, 1 | 3, 1 | 4, 1 | 5, 1 | 7, 1 | 8

Question 3: Given the following stem and leaf diagram: stems: 1, 2, 3; leaves: 4, 5, 7, 8, 9, 0, 2, 3, 5. Write an appropriate Key.

Answer: Key: tens digit | units digit

Question 4: A stem and leaf diagram shows data with stems: 4, 5, 6; leaves: 1, 3, 3, 7, 9, 0, 2, 4. Create a suitable Key.

Answer: Key: 10s | units

Question 5: Identify the mistake in this Key: 'Key: 2 | 0, 2 | 1, 2 | 2, 2 | 3,'

Answer: The mistake is the comma at the end; it should end with a period or no punctuation, and the key should be consistent.

Question 6: Create a stem and leaf diagram for the data: 21, 22, 23, 24, 25, 31, 32, 33, 34, 35. Then, write an appropriate Key.

Answer: Stems: 2, 3; Leaves: 1,2,3,4,5,1,2,3,4,5 Key: 10s | units

Question 7: A student creates a Key as 'Key: tens | units,' but the stem and leaf diagram shows only the units. Is the Key correct? Why or why not?

Answer: No, the Key implies a tens digit, but the diagram only shows units. The Key should match the data.

Question 8: Construct a stem and leaf diagram for the data: 45, 46, 47, 48, 49, 50, 51, 52, 53, 54. Then, write an accurate Key.

Answer: Stems: 4, 5; Leaves: 5,6,7,8,9,0,1,2,3,4 Key: 10s | units

Question 9: Identify a common mistake students make when creating Keys for stem and leaf diagrams and describe how to avoid it.

Answer: A common mistake is using inconsistent or incorrect notation. To avoid this, double-check the stems and leaves align properly with the data and clearly state what the key represents.

Question 10: Given a stem and leaf diagram with stems 3, 4, 5 and leaves 0, 3, 5, 7, 9, construct a matching Key.

Answer: Key: 10s | units

Question 11: Explain how an incorrect or missing Key can lead to misinterpretation of the data in a stem and leaf diagram.

Answer: Without a correct Key, students may misunderstand what the stems and leaves represent, leading to incorrect conclusions about the data distribution.