The task involves solving a series of mental addition problems with two-digit numbers. The goal is to add the numbers in each pair and write down the correct sums. Let's solve each problem step by step.
---
Problem 1: \( 57 + 58 \)
- Add the tens place: \( 50 + 50 = 100 \)
- Add the ones place: \( 7 + 8 = 15 \)
- Combine the results: \( 100 + 15 = 115 \)
Answer: \( 115 \)
---
Problem 2: \( 64 + 16 \)
- Add the tens place: \( 60 + 10 = 70 \)
- Add the ones place: \( 4 + 6 = 10 \)
- Combine the results: \( 70 + 10 = 80 \)
Answer: \( 80 \)
---
Problem 3: \( 97 + 53 \)
- Add the tens place: \( 90 + 50 = 140 \)
- Add the ones place: \( 7 + 3 = 10 \)
- Combine the results: \( 140 + 10 = 150 \)
Answer: \( 150 \)
---
Problem 4: \( 47 + 65 \)
- Add the tens place: \( 40 + 60 = 100 \)
- Add the ones place: \( 7 + 5 = 12 \)
- Combine the results: \( 100 + 12 = 112 \)
Answer: \( 112 \)
---
Problem 5: \( 55 + 65 \)
- Add the tens place: \( 50 + 60 = 110 \)
- Add the ones place: \( 5 + 5 = 10 \)
- Combine the results: \( 110 + 10 = 120 \)
Answer: \( 120 \)
---
Problem 6: \( 61 + 51 \)
- Add the tens place: \( 60 + 50 = 110 \)
- Add the ones place: \( 1 + 1 = 2 \)
- Combine the results: \( 110 + 2 = 112 \)
Answer: \( 112 \)
---
Problem 7: \( 75 + 75 \)
- Add the tens place: \( 70 + 70 = 140 \)
- Add the ones place: \( 5 + 5 = 10 \)
- Combine the results: \( 140 + 10 = 150 \)
Answer: \( 150 \)
---
Problem 8: \( 93 + 71 \)
- Add the tens place: \( 90 + 70 = 160 \)
- Add the ones place: \( 3 + 1 = 4 \)
- Combine the results: \( 160 + 4 = 164 \)
Answer: \( 164 \)
---
Problem 9: \( 54 + 33 \)
- Add the tens place: \( 50 + 30 = 80 \)
- Add the ones place: \( 4 + 3 = 7 \)
- Combine the results: \( 80 + 7 = 87 \)
Answer: \( 87 \)
---
Problem 10: \( 72 + 63 \)
- Add the tens place: \( 70 + 60 = 130 \)
- Add the ones place: \( 2 + 3 = 5 \)
- Combine the results: \( 130 + 5 = 135 \)
Answer: \( 135 \)
---
Problem 11: \( 75 + 43 \)
- Add the tens place: \( 70 + 40 = 110 \)
- Add the ones place: \( 5 + 3 = 8 \)
- Combine the results: \( 110 + 8 = 118 \)
Answer: \( 118 \)
---
Problem 12: \( 80 + 56 \)
- Add the tens place: \( 80 + 50 = 130 \)
- Add the ones place: \( 0 + 6 = 6 \)
- Combine the results: \( 130 + 6 = 136 \)
Answer: \( 136 \)
---
Problem 13: \( 43 + 38 \)
- Add the tens place: \( 40 + 30 = 70 \)
- Add the ones place: \( 3 + 8 = 11 \)
- Combine the results: \( 70 + 11 = 81 \)
Answer: \( 81 \)
---
Final Answers:
\[
\boxed{
\begin{array}{ll}
1. & 115 \\
2. & 80 \\
3. & 150 \\
4. & 112 \\
5. & 120 \\
6. & 112 \\
7. & 150 \\
8. & 164 \\
9. & 87 \\
10. & 135 \\
11. & 118 \\
12. & 136 \\
13. & 81 \\
\end{array}
}
\]
Parent Tip: Review the logic above to help your child master the concept of 100 addition facts worksheet.
