Students can use this worksheet to practice solving addition equations involving decimal numbers.

Problem: Addition with Decimals

The task is to solve the given addition problems involving decimals. Below are the solutions with step-by-step explanations.

---

#### Problem 1:
1. \( 45.3 + 9.9 = \)
- Align the decimal points:
```
45.3
+ 9.9
------
55.2
```
- Answer: \( 55.2 \)

2. \( 9.63 + 2.88 = \)
- Align the decimal points:
```
9.63
+ 2.88
------
12.51
```
- Answer: \( 12.51 \)

---

#### Problem 2:
1. \( 6.7 + 39.7 = \)
- Align the decimal points:
```
6.7
+ 39.7
------
46.4
```
- Answer: \( 46.4 \)

2. \( 5.74 + 9.9 = \)
- Align the decimal points (write \( 9.9 \) as \( 9.90 \)):
```
5.74
+ 9.90
------
15.64
```
- Answer: \( 15.64 \)

---

#### Problem 3:
1. \( 16.8 + 17.5 = \)
- Align the decimal points:
```
16.8
+ 17.5
------
34.3
```
- Answer: \( 34.3 \)

2. \( 4.12 + 6.31 = \)
- Align the decimal points:
```
4.12
+ 6.31
------
10.43
```
- Answer: \( 10.43 \)

---

#### Problem 4:
1. \( 9.2 + 8.8 = \)
- Align the decimal points:
```
9.2
+ 8.8
------
18.0
```
- Answer: \( 18.0 \)

2. \( 9.92 + 9.32 = \)
- Align the decimal points:
```
9.92
+ 9.32
------
19.24
```
- Answer: \( 19.24 \)

---

#### Problem 5:
1. \( 16.3 + 18.8 = \)
- Align the decimal points:
```
16.3
+ 18.8
------
35.1
```
- Answer: \( 35.1 \)

2. \( 74.3 + 83.5 = \)
- Align the decimal points:
```
74.3
+ 83.5
------
157.8
```
- Answer: \( 157.8 \)

---

#### Problem 6:
1. \( 2.53 + 4.5 = \)
- Align the decimal points (write \( 4.5 \) as \( 4.50 \)):
```
2.53
+ 4.50
------
7.03
```
- Answer: \( 7.03 \)

2. \( 4.21 + 9.6 = \)
- Align the decimal points (write \( 9.6 \) as \( 9.60 \)):
```
4.21
+ 9.60
------
13.81
```
- Answer: \( 13.81 \)

---

#### Problem 7:
1. \( 95.6 + 8.64 = \)
- Align the decimal points:
```
95.60
+ 8.64
------
104.24
```
- Answer: \( 104.24 \)

2. \( 47.3 + 52.9 = \)
- Align the decimal points:
```
47.3
+ 52.9
------
100.2
```
- Answer: \( 100.2 \)

---

#### Problem 8:
1. \( 17.7 + 22.3 = \)
- Align the decimal points:
```
17.7
+ 22.3
------
40.0
```
- Answer: \( 40.0 \)

2. \( 45.4 + 8.6 = \)
- Align the decimal points:
```
45.4
+ 8.6
------
54.0
```
- Answer: \( 54.0 \)

---

#### Problem 9:
1. \( 8.95 + 9.2 = \)
- Align the decimal points (write \( 9.2 \) as \( 9.20 \)):
```
8.95
+ 9.20
------
18.15
```
- Answer: \( 18.15 \)

2. \( 36.2 + 4.78 = \)
- Align the decimal points:
```
36.20
+ 4.78
------
40.98
```
- Answer: \( 40.98 \)

---

#### Problem 10:
1. \( 6.3 + 7.55 = \)
- Align the decimal points (write \( 6.3 \) as \( 6.30 \)):
```
6.30
+ 7.55
------
13.85
```
- Answer: \( 13.85 \)

2. \( 6.63 + 82.1 = \)
- Align the decimal points (write \( 82.1 \) as \( 82.10 \)):
```
6.63
+ 82.10
------
88.73
```
- Answer: \( 88.73 \)

---

Final Answers:

1. \( 55.2 \), \( 12.51 \)
2. \( 46.4 \), \( 15.64 \)
3. \( 34.3 \), \( 10.43 \)
4. \( 18.0 \), \( 19.24 \)
5. \( 35.1 \), \( 157.8 \)
6. \( 7.03 \), \( 13.81 \)
7. \( 104.24 \), \( 100.2 \)
8. \( 40.0 \), \( 54.0 \)
9. \( 18.15 \), \( 40.98 \)
10. \( 13.85 \), \( 88.73 \)

Boxed Final Answer:
\[
\boxed{
\begin{array}{ll}
1. & 55.2, \, 12.51 \\
2. & 46.4, \, 15.64 \\
3. & 34.3, \, 10.43 \\
4. & 18.0, \, 19.24 \\
5. & 35.1, \, 157.8 \\
6. & 7.03, \, 13.81 \\
7. & 104.24, \, 100.2 \\
8. & 40.0, \, 54.0 \\
9. & 18.15, \, 40.98 \\
10. & 13.85, \, 88.73 \\
\end{array}
}
\]