3-Digit Addition No Regrouping Worksheet

Problem Description:

The task involves solving 3-digit addition problems without regrouping. This means that when adding the digits in each column (ones, tens, hundreds), the sum should not exceed 9, so there is no need to carry over any values to the next column.

Given Problems:

1.
```
408
+501
----
```

2.
```
720
+170
----
```

3.
```
652
+37
----
```

4.
```
425
+423
----
```

5.
```
852
+146
----
```

6.
```
903
+93
----
```

Solution Approach:

For each problem, we will add the numbers digit by digit (starting from the ones place) and ensure that the sum in each column does not exceed 9. If it does, the problem would require regrouping, which is not allowed here.

---

Step-by-Step Solutions:

#### Problem 1:
```
408
+ 501
-----
```
- Ones place: \( 8 + 1 = 9 \)
- Tens place: \( 0 + 0 = 0 \)
- Hundreds place: \( 4 + 5 = 9 \)

Result:
```
408
+ 501
-----
909
```

#### Problem 2:
```
720
+ 170
-----
```
- Ones place: \( 0 + 0 = 0 \)
- Tens place: \( 2 + 7 = 9 \)
- Hundreds place: \( 7 + 1 = 8 \)

Result:
```
720
+ 170
-----
890
```

#### Problem 3:
```
652
+ 37
-----
```
- Ones place: \( 2 + 7 = 9 \)
- Tens place: \( 5 + 3 = 8 \)
- Hundreds place: \( 6 + 0 = 6 \)

Result:
```
652
+ 37
-----
689
```

#### Problem 4:
```
425
+ 423
-----
```
- Ones place: \( 5 + 3 = 8 \)
- Tens place: \( 2 + 2 = 4 \)
- Hundreds place: \( 4 + 4 = 8 \)

Result:
```
425
+ 423
-----
848
```

#### Problem 5:
```
852
+ 146
-----
```
- Ones place: \( 2 + 6 = 8 \)
- Tens place: \( 5 + 4 = 9 \)
- Hundreds place: \( 8 + 1 = 9 \)

Result:
```
852
+ 146
-----
998
```

#### Problem 6:
```
903
+ 93
-----
```
- Ones place: \( 3 + 3 = 6 \)
- Tens place: \( 0 + 9 = 9 \)
- Hundreds place: \( 9 + 0 = 9 \)

Result:
```
903
+ 93
-----
996
```

---

Final Answers:

1. \( 408 + 501 = 909 \)
2. \( 720 + 170 = 890 \)
3. \( 652 + 37 = 689 \)
4. \( 425 + 423 = 848 \)
5. \( 852 + 146 = 998 \)
6. \( 903 + 93 = 996 \)

\boxed{
\begin{aligned}
&909 \\
&890 \\
&689 \\
&848 \\
&998 \\
&996
\end{aligned}
}