3rd Grade Math Worksheet with addition problems for students to solve.

Problem Description:

The task is to solve a series of addition problems from a 3rd-grade math worksheet. Each problem involves adding two numbers together. We will solve each problem step by step.

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Solution:

#### Row 1:
1. 124 + 21
- Add the ones place: \( 4 + 1 = 5 \)
- Add the tens place: \( 2 + 2 = 4 \)
- Add the hundreds place: \( 1 + 0 = 1 \)
- Result: \( 124 + 21 = 145 \)

2. 141 + 16
- Add the ones place: \( 1 + 6 = 7 \)
- Add the tens place: \( 4 + 1 = 5 \)
- Add the hundreds place: \( 1 + 0 = 1 \)
- Result: \( 141 + 16 = 157 \)

3. 167 + 26
- Add the ones place: \( 7 + 6 = 13 \) (write down 3, carry over 1)
- Add the tens place: \( 6 + 2 + 1 = 9 \)
- Add the hundreds place: \( 1 + 0 = 1 \)
- Result: \( 167 + 26 = 193 \)

4. 174 + 15
- Add the ones place: \( 4 + 5 = 9 \)
- Add the tens place: \( 7 + 1 = 8 \)
- Add the hundreds place: \( 1 + 0 = 1 \)
- Result: \( 174 + 15 = 189 \)

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#### Row 2:
5. 205 + 65
- Add the ones place: \( 5 + 5 = 10 \) (write down 0, carry over 1)
- Add the tens place: \( 0 + 6 + 1 = 7 \)
- Add the hundreds place: \( 2 + 0 = 2 \)
- Result: \( 205 + 65 = 270 \)

6. 219 + 78
- Add the ones place: \( 9 + 8 = 17 \) (write down 7, carry over 1)
- Add the tens place: \( 1 + 7 + 1 = 9 \)
- Add the hundreds place: \( 2 + 0 = 2 \)
- Result: \( 219 + 78 = 297 \)

7. 246 + 54
- Add the ones place: \( 6 + 4 = 10 \) (write down 0, carry over 1)
- Add the tens place: \( 4 + 5 + 1 = 10 \) (write down 0, carry over 1)
- Add the hundreds place: \( 2 + 0 + 1 = 3 \)
- Result: \( 246 + 54 = 300 \)

8. 439 + 62
- Add the ones place: \( 9 + 2 = 11 \) (write down 1, carry over 1)
- Add the tens place: \( 3 + 6 + 1 = 10 \) (write down 0, carry over 1)
- Add the hundreds place: \( 4 + 0 + 1 = 5 \)
- Result: \( 439 + 62 = 501 \)

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#### Row 3:
9. 104 + 103
- Add the ones place: \( 4 + 3 = 7 \)
- Add the tens place: \( 0 + 0 = 0 \)
- Add the hundreds place: \( 1 + 1 = 2 \)
- Result: \( 104 + 103 = 207 \)

10. 146 + 120
- Add the ones place: \( 6 + 0 = 6 \)
- Add the tens place: \( 4 + 2 = 6 \)
- Add the hundreds place: \( 1 + 1 = 2 \)
- Result: \( 146 + 120 = 266 \)

11. 174 + 147
- Add the ones place: \( 4 + 7 = 11 \) (write down 1, carry over 1)
- Add the tens place: \( 7 + 4 + 1 = 12 \) (write down 2, carry over 1)
- Add the hundreds place: \( 1 + 1 + 1 = 3 \)
- Result: \( 174 + 147 = 321 \)

12. 136 + 127
- Add the ones place: \( 6 + 7 = 13 \) (write down 3, carry over 1)
- Add the tens place: \( 3 + 2 + 1 = 6 \)
- Add the hundreds place: \( 1 + 1 = 2 \)
- Result: \( 136 + 127 = 263 \)

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#### Row 4:
13. 208 + 193
- Add the ones place: \( 8 + 3 = 11 \) (write down 1, carry over 1)
- Add the tens place: \( 0 + 9 + 1 = 10 \) (write down 0, carry over 1)
- Add the hundreds place: \( 2 + 1 + 1 = 4 \)
- Result: \( 208 + 193 = 401 \)

14. 615 + 310
- Add the ones place: \( 5 + 0 = 5 \)
- Add the tens place: \( 1 + 1 = 2 \)
- Add the hundreds place: \( 6 + 3 = 9 \)
- Result: \( 615 + 310 = 925 \)

15. 454 + 342
- Add the ones place: \( 4 + 2 = 6 \)
- Add the tens place: \( 5 + 4 = 9 \)
- Add the hundreds place: \( 4 + 3 = 7 \)
- Result: \( 454 + 342 = 796 \)

16. 626 + 321
- Add the ones place: \( 6 + 1 = 7 \)
- Add the tens place: \( 2 + 2 = 4 \)
- Add the hundreds place: \( 6 + 3 = 9 \)
- Result: \( 626 + 321 = 947 \)

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Final Answers:

\[
\begin{aligned}
&124 + 21 = 145 \\
&141 + 16 = 157 \\
&167 + 26 = 193 \\
&174 + 15 = 189 \\
&205 + 65 = 270 \\
&219 + 78 = 297 \\
&246 + 54 = 300 \\
&439 + 62 = 501 \\
&104 + 103 = 207 \\
&146 + 120 = 266 \\
&174 + 147 = 321 \\
&136 + 127 = 263 \\
&208 + 193 = 401 \\
&615 + 310 = 925 \\
&454 + 342 = 796 \\
&626 + 321 = 947 \\
\end{aligned}
\]

\boxed{
\begin{array}{cccc}
145 & 157 & 193 & 189 \\
270 & 297 & 300 & 501 \\
207 & 266 & 321 & 263 \\
401 & 925 & 796 & 947 \\
\end{array}
}