Add fractions worksheet with visual aids for solving addition problems.

To solve the problems in the worksheet, we need to determine the missing fractions that complete each addition calculation. Let's go through each problem step by step.

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Problem 1 (Already Solved)

$$
\frac{2}{6} + \frac{3}{6} = \frac{5}{6}
$$
The image shows a circle divided into 6 equal parts, with 5 parts shaded. This confirms the solution.

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Problem 2

$$
\frac{3}{10} + \frac{\square}{10} = \frac{7}{10}
$$
- The denominator is 10, so we only need to focus on the numerators.
- We need to find a number \( x \) such that:
$$
3 + x = 7
$$
- Solving for \( x \):
$$
x = 7 - 3 = 4
$$
- Therefore:
$$
\frac{3}{10} + \frac{4}{10} = \frac{7}{10}
$$

Answer:
$$
\boxed{4}
$$

---

Problem 3

$$
\frac{4}{8} + \frac{\square}{8} = \frac{7}{8}
$$
- The denominator is 8, so we only need to focus on the numerators.
- We need to find a number \( x \) such that:
$$
4 + x = 7
$$
- Solving for \( x \):
$$
x = 7 - 4 = 3
$$
- Therefore:
$$
\frac{4}{8} + \frac{3}{8} = \frac{7}{8}
$$

Answer:
$$
\boxed{3}
$$

---

Problem 4

$$
\frac{1}{5} + \frac{\square}{5} = \frac{4}{5}
$$
- The denominator is 5, so we only need to focus on the numerators.
- We need to find a number \( x \) such that:
$$
1 + x = 4
$$
- Solving for \( x \):
$$
x = 4 - 1 = 3
$$
- Therefore:
$$
\frac{1}{5} + \frac{3}{5} = \frac{4}{5}
$$

Answer:
$$
\boxed{3}
$$

---

Problem 5

$$
\frac{2}{7} + \frac{\square}{7} = \frac{5}{7}
$$
- The denominator is 7, so we only need to focus on the numerators.
- We need to find a number \( x \) such that:
$$
2 + x = 5
$$
- Solving for \( x \):
$$
x = 5 - 2 = 3
$$
- Therefore:
$$
\frac{2}{7} + \frac{3}{7} = \frac{5}{7}
$$

Answer:
$$
\boxed{3}
$$

---

Problem 6

$$
\frac{5}{9} + \frac{\square}{9} = \frac{8}{9}
$$
- The denominator is 9, so we only need to focus on the numerators.
- We need to find a number \( x \) such that:
$$
5 + x = 8
$$
- Solving for \( x \):
$$
x = 8 - 5 = 3
$$
- Therefore:
$$
\frac{5}{9} + \frac{3}{9} = \frac{8}{9}
$$

Answer:
$$
\boxed{3}
$$

---

Problem 7

$$
\frac{6}{10} + \frac{\square}{10} = \frac{10}{10}
$$
- The denominator is 10, so we only need to focus on the numerators.
- We need to find a number \( x \) such that:
$$
6 + x = 10
$$
- Solving for \( x \):
$$
x = 10 - 6 = 4
$$
- Therefore:
$$
\frac{6}{10} + \frac{4}{10} = \frac{10}{10}
$$

Answer:
$$
\boxed{4}
$$

---

Problem 8

$$
\frac{3}{6} + \frac{\square}{6} = \frac{6}{6}
$$
- The denominator is 6, so we only need to focus on the numerators.
- We need to find a number \( x \) such that:
$$
3 + x = 6
$$
- Solving for \( x \):
$$
x = 6 - 3 = 3
$$
- Therefore:
$$
\frac{3}{6} + \frac{3}{6} = \frac{6}{6}
$$

Answer:
$$
\boxed{3}
$$

---

Problem 9

$$
\frac{2}{8} + \frac{\square}{8} = \frac{6}{8}
$$
- The denominator is 8, so we only need to focus on the numerators.
- We need to find a number \( x \) such that:
$$
2 + x = 6
$$
- Solving for \( x \):
$$
x = 6 - 2 = 4
$$
- Therefore:
$$
\frac{2}{8} + \frac{4}{8} = \frac{6}{8}
$$

Answer:
$$
\boxed{4}
$$

---

Problem 10

$$
\frac{4}{9} + \frac{\square}{9} = \frac{8}{9}
$$
- The denominator is 9, so we only need to focus on the numerators.
- We need to find a number \( x \) such that:
$$
4 + x = 8
$$
- Solving for \( x \):
$$
x = 8 - 4 = 4
$$
- Therefore:
$$
\frac{4}{9} + \frac{4}{9} = \frac{8}{9}
$$

Answer:
$$
\boxed{4}
$$

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Final Answers:

1. \( \boxed{3} \)
2. \( \boxed{4} \)
3. \( \boxed{3} \)
4. \( \boxed{3} \)
5. \( \boxed{3} \)
6. \( \boxed{3} \)
7. \( \boxed{4} \)
8. \( \boxed{3} \)
9. \( \boxed{4} \)
10. \( \boxed{4} \)

$$
\boxed{3, 4, 3, 3, 3, 3, 4, 3, 4, 4}
$$