Question

The stem-and-leaf plot below gives the test scores for the 21 students in Ms. Carter's science class. Use the plot to answer the questions that follow.
Test score
6 | 1 6
7 | 0 3 3 5 6 8 9
8 | 1 1 3 4 5 5 8 8
9 | 0 2 6 7
Key: 6/1 means a score of 61.
(a) What was the lowest score overall?
(b) How many students scored in the 70s?
(c) What was the highest score in the 80s?

Answer 1

To interpret the stem-and-leaf plot:

- The **stem** represents the tens place, while the **leaves** represent the units place of the scores.

From the plot:
- **Stem 6:** The scores are 61, 66.
- **Stem 7:** The scores are 70, 73, 73, 75, 76, 78, 79.
- **Stem 8:** The scores are 81, 81, 83, 84, 85, 85, 88, 88.
- **Stem 9:** The scores are 90, 92, 96, 97.

Now to answer the questions:

(a) **What was the lowest score overall?**
- The lowest score is represented by the smallest number in the plot, which is **61**.

(b) **How many students scored in the 70s?**
- The scores in the 70s are: 70, 73, 73, 75, 76, 78, 79.
- Counting these gives us a total of **7 students**.

(c) **What was the highest score in the 80s?**
- The highest score in the 80s is represented by the highest number for the stem of 8, which is **88**.

So the answers are:
(a) 61
(b) 7
(c) 88