Stem and Leaf Plots Notes and Worksheets - Lindsay Bowden - Free Printable

Absolutely! Let’s solve this step by step.

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## 🔹 Part 1: Fill in the blanks

> Stem and leaf plot – a table used to organize data and show the distribution of data values
> The stem is usually the first one or two digits and the leaf the last digit.

✔ *Explanation*: A stem-and-leaf plot visually displays how data is spread out. The “stem” holds the leading digit(s), and the “leaf” holds the final digit — making it easy to see patterns, clusters, and outliers.

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## 🔹 Part 2: Create the Stem-and-Leaf Plot

Given grades:
89, 85, 75, 76, 63, 90, 88, 94, 71, 54, 95, 79, 83, 85

Step 1: Sort the data (optional but helpful)

Sorted:
54, 63, 71, 75, 76, 79, 83, 85, 85, 88, 89, 90, 94, 95

Step 2: Determine stems and leaves

- Stems = tens digit
- Leaves = ones digit

So:

```
Stem | Leaf
-----|-----
5 | 4
6 | 3
7 | 1 5 6 9
8 | 3 5 5 8 9
9 | 0 4 5
```

✔ *Note*: We write leaves in order from smallest to largest within each stem.

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## 🔹 Part 3: Answer the Questions

We have 14 total students.

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1. What is the range?

> Range = Maximum value – Minimum value

Max = 95
Min = 54
→ Range = 95 – 54 = 41

✔ Answer: 41

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2. What is the mode?

> Mode = Most frequently occurring value

Look at the list:
85 appears twice — all others appear once.

✔ Answer: 85

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3. What is the mean?

> Mean = Sum of all values ÷ Number of values

Sum = 54 + 63 + 71 + 75 + 76 + 79 + 83 + 85 + 85 + 88 + 89 + 90 + 94 + 95
Let’s add step-by-step:

- 54 + 63 = 117
- +71 = 188
- +75 = 263
- +76 = 339
- +79 = 418
- +83 = 501
- +85 = 586
- +85 = 671
- +88 = 759
- +89 = 848
- +90 = 938
- +94 = 1032
- +95 = 1127

Number of values = 14

Mean = 1127 ÷ 14 = 80.5

✔ Answer: 80.5

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4. What is the median?

> Median = Middle value when data is ordered

We have 14 values → even number → median = average of 7th and 8th values.

Ordered list:
1. 54
2. 63
3. 71
4. 75
5. 76
6. 79
7. 83 ← 7th
8. 85 ← 8th
9. 85
10. 88
11. 89
12. 90
13. 94
14. 95

Median = (83 + 85) ÷ 2 = 84

✔ Answer: 84

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5. Which stem has the most leaves? What does that mean?

Look at the plot:

- Stem 5: 1 leaf
- Stem 6: 1 leaf
- Stem 7: 4 leaves → 71, 75, 76, 79
- Stem 8: 5 leaves → 83, 85, 85, 88, 89 ← ✔ Most leaves
- Stem 9: 3 leaves

✔ Answer: Stem 8 has the most leaves (5).
This means more students scored in the 80s than any other decade, indicating the class performed best in that range.

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6. What percentage of the class scored 80 or higher?

Scores ≥ 80:
From sorted list:
83, 85, 85, 88, 89, 90, 94, 95 → 8 scores

Total students = 14

Percentage = (8 ÷ 14) × 100 ≈ 57.14%

✔ Answer: Approximately 57.1%

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7. What percentage of the students failed the class (69 or less)?

“Failed” = ≤ 69

Scores ≤ 69:
54, 63 → 2 scores

Percentage = (2 ÷ 14) × 100 ≈ 14.29%

✔ Answer: Approximately 14.3%

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## ✔ Final Answers Summary:

1. Range: 41
2. Mode: 85
3. Mean: 80.5
4. Median: 84
5. Stem with most leaves: 8 → Most students scored in the 80s
6. % scoring 80 or higher: ≈57.1%
7. % failing (≤69): ≈14.3%

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Let me know if you’d like this turned into a printable worksheet or need help explaining any part further! 📊📚