Add and Subtract Decimals: Missing Digits - Math Worksheets - Free Printable

To solve the problems involving addition and subtraction of decimals to the thousandths place, we need to carefully align the decimal points and perform the operations step by step. Let's go through each problem:

---

Problem 1: \( 3.897 + 1.127 \)

1. Align the decimal points:
```
3.897
+ 1.127
```

2. Add column by column from right to left:
- Thousandths place: \( 7 + 7 = 14 \) → Write 4, carry 1.
- Hundredths place: \( 9 + 2 + 1 (\text{carry}) = 12 \) → Write 2, carry 1.
- Tenths place: \( 8 + 1 + 1 (\text{carry}) = 10 \) → Write 0, carry 1.
- Ones place: \( 3 + 1 + 1 (\text{carry}) = 5 \).

3. Result:
```
3.897
+ 1.127
------
5.024
```

Answer: \( 5.024 \)

---

Problem 2: \( 9.387 - 1.819 \)

1. Align the decimal points:
```
9.387
- 1.819
```

2. Subtract column by column from right to left:
- Thousandths place: \( 7 - 9 \). Borrow 1 from the hundredths place: \( 17 - 9 = 8 \).
- Hundredths place: \( 8 - 1 - 1 (\text{borrow}) = 6 \).
- Tenths place: \( 3 - 8 \). Borrow 1 from the ones place: \( 13 - 8 = 5 \).
- Ones place: \( 9 - 1 - 1 (\text{borrow}) = 7 \).

3. Result:
```
9.387
- 1.819
------
7.568
```

Answer: \( 7.568 \)

---

Problem 3: \( 1.944 - 1.174 \)

1. Align the decimal points:
```
1.944
- 1.174
```

2. Subtract column by column from right to left:
- Thousandths place: \( 4 - 4 = 0 \).
- Hundredths place: \( 4 - 7 \). Borrow 1 from the tenths place: \( 14 - 7 = 7 \).
- Tenths place: \( 9 - 1 - 1 (\text{borrow}) = 7 \).
- Ones place: \( 1 - 1 = 0 \).

3. Result:
```
1.944
- 1.174
------
0.770
```

Answer: \( 0.770 \)

---

Problem 4: \( 5.234 + 4.199 \)

1. Align the decimal points:
```
5.234
+ 4.199
```

2. Add column by column from right to left:
- Thousandths place: \( 4 + 9 = 13 \) → Write 3, carry 1.
- Hundredths place: \( 3 + 9 + 1 (\text{carry}) = 13 \) → Write 3, carry 1.
- Tenths place: \( 2 + 1 + 1 (\text{carry}) = 4 \).
- Ones place: \( 5 + 4 = 9 \).

3. Result:
```
5.234
+ 4.199
------
9.433
```

Answer: \( 9.433 \)

---

Problem 5: \( 3.092 - 1.308 \)

1. Align the decimal points:
```
3.092
- 1.308
```

2. Subtract column by column from right to left:
- Thousandths place: \( 2 - 8 \). Borrow 1 from the hundredths place: \( 12 - 8 = 4 \).
- Hundredths place: \( 9 - 0 - 1 (\text{borrow}) = 8 \).
- Tenths place: \( 0 - 3 \). Borrow 1 from the ones place: \( 10 - 3 = 7 \).
- Ones place: \( 3 - 1 - 1 (\text{borrow}) = 1 \).

3. Result:
```
3.092
- 1.308
------
1.784
```

Answer: \( 1.784 \)

---

Problem 6: \( 4.448 - 3.432 \)

1. Align the decimal points:
```
4.448
- 3.432
```

2. Subtract column by column from right to left:
- Thousandths place: \( 8 - 2 = 6 \).
- Hundredths place: \( 4 - 3 = 1 \).
- Tenths place: \( 4 - 4 = 0 \).
- Ones place: \( 4 - 3 = 1 \).

3. Result:
```
4.448
- 3.432
------
1.016
```

Answer: \( 1.016 \)

---

Problem 7: \( 9.423 + 3.231 \)

1. Align the decimal points:
```
9.423
+ 3.231
```

2. Add column by column from right to left:
- Thousandths place: \( 3 + 1 = 4 \).
- Hundredths place: \( 2 + 3 = 5 \).
- Tenths place: \( 4 + 2 = 6 \).
- Ones place: \( 9 + 3 = 12 \) → Write 2, carry 1.

3. Result:
```
9.423
+ 3.231
------
12.654
```

Answer: \( 12.654 \)

---

Problem 8: \( 4.982 - 2.999 \)

1. Align the decimal points:
```
4.982
- 2.999
```

2. Subtract column by column from right to left:
- Thousandths place: \( 2 - 9 \). Borrow 1 from the hundredths place: \( 12 - 9 = 3 \).
- Hundredths place: \( 8 - 9 - 1 (\text{borrow}) = 8 - 10 = -2 \). Borrow 1 from the tenths place: \( 18 - 9 - 1 = 8 \).
- Tenths place: \( 9 - 9 - 1 (\text{borrow}) = 8 \).
- Ones place: \( 4 - 2 - 1 (\text{borrow}) = 1 \).

3. Result:
```
4.982
- 2.999
------
1.983
```

Answer: \( 1.983 \)

---

Problem 9: \( 7.224 + 6.331 \)

1. Align the decimal points:
```
7.224
+ 6.331
```

2. Add column by column from right to left:
- Thousandths place: \( 4 + 1 = 5 \).
- Hundredths place: \( 2 + 3 = 5 \).
- Tenths place: \( 2 + 3 = 5 \).
- Ones place: \( 7 + 6 = 13 \) → Write 3, carry 1.

3. Result:
```
7.224
+ 6.331
------
13.555
```

Answer: \( 13.555 \)

---

Problem 10: \( 6.104 - 5.503 \)

1. Align the decimal points:
```
6.104
- 5.503
```

2. Subtract column by column from right to left:
- Thousandths place: \( 4 - 3 = 1 \).
- Hundredths place: \( 0 - 0 = 0 \).
- Tenths place: \( 1 - 5 \). Borrow 1 from the ones place: \( 11 - 5 = 6 \).
- Ones place: \( 6 - 5 - 1 (\text{borrow}) = 0 \).

3. Result:
```
6.104
- 5.503
------
0.601
```

Answer: \( 0.601 \)

---

Problem 11: \( 5.204 + 5.199 \)

1. Align the decimal points:
```
5.204
+ 5.199
```

2. Add column by column from right to left:
- Thousandths place: \( 4 + 9 = 13 \) → Write 3, carry 1.
- Hundredths place: \( 0 + 9 + 1 (\text{carry}) = 10 \) → Write 0, carry 1.
- Tenths place: \( 2 + 1 + 1 (\text{carry}) = 4 \).
- Ones place: \( 5 + 5 = 10 \) → Write 0, carry 1.

3. Result:
```
5.204
+ 5.199
------
10.403
```

Answer: \( 10.403 \)

---

Problem 12: \( 6.290 + 8.980 \)

1. Align the decimal points:
```
6.290
+ 8.980
```

2. Add column by column from right to left:
- Thousandths place: \( 0 + 0 = 0 \).
- Hundredths place: \( 9 + 8 = 17 \) → Write 7, carry 1.
- Tenths place: \( 2 + 9 + 1 (\text{carry}) = 12 \) → Write 2, carry 1.
- Ones place: \( 6 + 8 + 1 (\text{carry}) = 15 \) → Write 5, carry 1.

3. Result:
```
6.290
+ 8.980
------
15.270
```

Answer: \( 15.270 \)

---

Problem 13: \( 0.987 + 3.442 \)

1. Align the decimal points:
```
0.987
+ 3.442
```

2. Add column by column from right to left:
- Thousandths place: \( 7 + 2 = 9 \).
- Hundredths place: \( 8 + 4 = 12 \) → Write 2, carry 1.
- Tenths place: \( 9 + 4 + 1 (\text{carry}) = 14 \) → Write 4, carry 1.
- Ones place: \( 0 + 3 + 1 (\text{carry}) = 4 \).

3. Result:
```
0.987
+ 3.442
------
4.429
```

Answer: \( 4.429 \)

---

Problem 14: \( 7.434 + 6.177 \)

1. Align the decimal points:
```
7.434
+ 6.177
```

2. Add column by column from right to left:
- Thousandths place: \( 4 + 7 = 11 \) → Write 1, carry 1.
- Hundredths place: \( 3 + 7 + 1 (\text{carry}) = 11 \) → Write 1, carry 1.
- Tenths place: \( 4 + 1 + 1 (\text{carry}) = 6 \).
- Ones place: \( 7 + 6 = 13 \) → Write 3, carry 1.

3. Result:
```
7.434
+ 6.177
------
13.611
```

Answer: \( 13.611 \)

---

Problem 15: \( 3.997 - 2.813 \)

1. Align the decimal points:
```
3.997
- 2.813
```

2. Subtract column by column from right to left:
- Thousandths place: \( 7 - 3 = 4 \).
- Hundredths place: \( 9 - 1 = 8 \).
- Tenths place: \( 9 - 8 = 1 \).
- Ones place: \( 3 - 2 = 1 \).

3. Result:
```
3.997
- 2.813
------
1.184
```

Answer: \( 1.184 \)

---

Problem 16: \( 3.143 - 0.198 \)

1. Align the decimal points:
```
3.143
- 0.198
```

2. Subtract column by column from right to left:
- Thousandths place: \( 3 - 8 \). Borrow 1 from the hundredths place: \( 13 - 8 = 5 \).
- Hundredths place: \( 4 - 9 - 1 (\text{borrow}) = 4 - 10 = -6 \). Borrow 1 from the tenths place: \( 14 - 9 - 1 = 4 \).
- Tenths place: \( 1 - 1 - 1 (\text{borrow}) = 0 \).
- Ones place: \( 3 - 0 = 3 \).

3. Result:
```
3.143
- 0.198
------
2.945
```

Answer: \( 2.945 \)

---

Final Answers:

\[
\boxed{
\begin{array}{ll}
1. & 5.024 \\
2. & 7.568 \\
3. & 0.770 \\
4. & 9.433 \\
5. & 1.784 \\
6. & 1.016 \\
7. & 12.654 \\
8. & 1.983 \\
9. & 13.555 \\
10. & 0.601 \\
11. & 10.403 \\
12. & 15.270 \\
13. & 4.429 \\
14. & 13.611 \\
15. & 1.184 \\
16. & 2.945 \\
\end{array}
}
\]