Problem Description:
The task is to solve a set of addition and subtraction problems for Grade 3 students. The goal is to practice mental arithmetic skills. Below are the problems presented in the image, organized into three columns.
Problems:
#### Column 1: Subtraction
1. \( 13 - 7 \)
2. \( 21 - 2 \)
3. \( 16 - 11 \)
4. \( 10 - 7 \)
5. \( 15 - 9 \)
6. \( 27 - 11 \)
#### Column 2: Addition
1. \( 12 + 5 \)
2. \( 12 + 13 \)
3. \( 11 + 9 \)
4. \( 3 + 18 \)
5. \( 23 + 15 \)
6. \( 7 + 15 \)
#### Column 3: Mixed Operations
1. \( 13 + 9 \)
2. \( 22 - 7 \)
3. \( 16 + 8 \)
4. \( 15 - 6 \)
5. \( 12 + 19 \)
6. \( 22 - 5 \)
Solution:
#### Column 1: Subtraction
1. \( 13 - 7 = 6 \)
- Subtract 7 from 13: \( 13 - 7 = 6 \).
2. \( 21 - 2 = 19 \)
- Subtract 2 from 21: \( 21 - 2 = 19 \).
3. \( 16 - 11 = 5 \)
- Subtract 11 from 16: \( 16 - 11 = 5 \).
4. \( 10 - 7 = 3 \)
- Subtract 7 from 10: \( 10 - 7 = 3 \).
5. \( 15 - 9 = 6 \)
- Subtract 9 from 15: \( 15 - 9 = 6 \).
6. \( 27 - 11 = 16 \)
- Subtract 11 from 27: \( 27 - 11 = 16 \).
#### Column 2: Addition
1. \( 12 + 5 = 17 \)
- Add 5 to 12: \( 12 + 5 = 17 \).
2. \( 12 + 13 = 25 \)
- Add 13 to 12: \( 12 + 13 = 25 \).
3. \( 11 + 9 = 20 \)
- Add 9 to 11: \( 11 + 9 = 20 \).
4. \( 3 + 18 = 21 \)
- Add 18 to 3: \( 3 + 18 = 21 \).
5. \( 23 + 15 = 38 \)
- Add 15 to 23: \( 23 + 15 = 38 \).
6. \( 7 + 15 = 22 \)
- Add 15 to 7: \( 7 + 15 = 22 \).
#### Column 3: Mixed Operations
1. \( 13 + 9 = 22 \)
- Add 9 to 13: \( 13 + 9 = 22 \).
2. \( 22 - 7 = 15 \)
- Subtract 7 from 22: \( 22 - 7 = 15 \).
3. \( 16 + 8 = 24 \)
- Add 8 to 16: \( 16 + 8 = 24 \).
4. \( 15 - 6 = 9 \)
- Subtract 6 from 15: \( 15 - 6 = 9 \).
5. \( 12 + 19 = 31 \)
- Add 19 to 12: \( 12 + 19 = 31 \).
6. \( 22 - 5 = 17 \)
- Subtract 5 from 22: \( 22 - 5 = 17 \).
Final Answers:
\[
\boxed{
\begin{array}{ccc}
6 & 17 & 22 \\
19 & 25 & 15 \\
5 & 20 & 24 \\
3 & 21 & 9 \\
6 & 38 & 31 \\
16 & 22 & 17 \\
\end{array}
}
\]
Parent Tip: Review the logic above to help your child master the concept of mental math worksheet.
