Worksheet for practicing three-digit addition using base-ten blocks.

It looks like you've uploaded a worksheet titled "THREE DIGIT ADDITION" that uses base-ten blocks (also known as place value blocks) to help students visually understand how to add three-digit numbers. The instructions say:

> "Use the blocks to add. First, add the ones. Next, add the tens. Last, add the hundreds."

Let's go through each problem step by step, using the base-ten block representations and solving the addition.

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🔢 Understanding Base-Ten Blocks:

- Small squares = Ones (value of 1)
- Long rods = Tens (value of 10)
- Large squares = Hundreds (value of 100)

We’ll solve each problem by:
1. Counting the ones
2. Counting the tens
3. Counting the hundreds
4. Adding them together

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## ✔ Problem 1:
```
156
+ 132
-----
```

Step 1: Add the ones

- 6 ones + 2 ones = 8 ones

Step 2: Add the tens

- 5 tens + 3 tens = 8 tens

Step 3: Add the hundreds

- 1 hundred + 1 hundred = 2 hundreds

Final Sum:

- 2 hundreds + 8 tens + 8 ones = 288

✔ Answer: 288

---

## ✔ Problem 2:
```
243
+ 122
-----
```

Step 1: Ones

- 3 + 2 = 5 ones

Step 2: Tens

- 4 tens + 2 tens = 6 tens

Step 3: Hundreds

- 2 + 1 = 3 hundreds

Final Sum:

- 3 hundreds + 6 tens + 5 ones = 365

✔ Answer: 365

---

## ✔ Problem 3:
```
313
+ 284
-----
```

Step 1: Ones

- 3 + 4 = 7 ones

Step 2: Tens

- 1 ten + 8 tens = 9 tens

Step 3: Hundreds

- 3 + 2 = 5 hundreds

Final Sum:

- 5 hundreds + 9 tens + 7 ones = 597

✔ Answer: 597

---

## ✔ Problem 4:
```
426
+ 311
-----
```

Step 1: Ones

- 6 + 1 = 7 ones

Step 2: Tens

- 2 tens + 1 ten = 3 tens

Step 3: Hundreds

- 4 + 3 = 7 hundreds

Final Sum:

- 7 hundreds + 3 tens + 7 ones = 737

✔ Answer: 737

---

## ✔ Problem 5:
```
361
+ 223
-----
```

Step 1: Ones

- 1 + 3 = 4 ones

Step 2: Tens

- 6 tens + 2 tens = 8 tens

Step 3: Hundreds

- 3 + 2 = 5 hundreds

Final Sum:

- 5 hundreds + 8 tens + 4 ones = 584

✔ Answer: 584

---

## ✔ Problem 6:
```
638
+ 201
-----
```

Step 1: Ones

- 8 + 1 = 9 ones

Step 2: Tens

- 3 tens + 0 tens = 3 tens

Step 3: Hundreds

- 6 + 2 = 8 hundreds

Final Sum:

- 8 hundreds + 3 tens + 9 ones = 839

✔ Answer: 839

---

📌 Summary of Answers:

| Problem | Addition | Answer |
|--------|------------------|--------|
| 1 | 156 + 132 | 288 |
| 2 | 243 + 122 | 365 |
| 3 | 313 + 284 | 597 |
| 4 | 426 + 311 | 737 |
| 5 | 361 + 223 | 584 |
| 6 | 638 + 201 | 839 |

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✔ How to Fill in the Worksheet:

For each problem:
1. Write the sum in the blank box.
2. Use the base-ten blocks shown to verify your answer (e.g., count the blocks for each place value).
3. Make sure the total matches the number you calculated.

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Let me know if you'd like this formatted as a printable answer key or want to turn it into a teaching guide!