Adding and Subtracting with Facts From 1 to 20 (A) - Free Printable

The image you provided is a worksheet titled "Add and Subtract (A)" from Math-Drills.com. The task involves solving each addition or subtraction problem listed in the grid. Below, I will explain how to solve these problems step by step.

General Approach:

1. Identify the operation: Each row contains either addition (`+`) or subtraction (`-`).
2. Perform the calculation:
- For addition, sum the two numbers.
- For subtraction, subtract the second number from the first.
3. Write the result in the space provided.

Example Problems:

Let's solve a few problems from the worksheet to illustrate the process:

#### Row 1:
1. \( 12 + 6 \)
- Add: \( 12 + 6 = 18 \)

2. \( 28 - 14 \)
- Subtract: \( 28 - 14 = 14 \)

3. \( 16 + 9 \)
- Add: \( 16 + 9 = 25 \)

4. \( 3 + 7 \)
- Add: \( 3 + 7 = 10 \)

#### Row 2:
1. \( 11 + 8 \)
- Add: \( 11 + 8 = 19 \)

2. \( 10 + 12 \)
- Add: \( 10 + 12 = 22 \)

3. \( 6 + 19 \)
- Add: \( 6 + 19 = 25 \)

4. \( 38 - 18 \)
- Subtract: \( 38 - 18 = 20 \)

#### Row 3:
1. \( 19 + 2 \)
- Add: \( 19 + 2 = 21 \)

2. \( 16 + 14 \)
- Add: \( 16 + 14 = 30 \)

3. \( 12 + 8 \)
- Add: \( 12 + 8 = 20 \)

4. \( 10 - 9 \)
- Subtract: \( 10 - 9 = 1 \)

Complete Solution:

Here are the solutions for all the problems in the worksheet:

#### Row 1:
- \( 12 + 6 = 18 \)
- \( 28 - 14 = 14 \)
- \( 16 + 9 = 25 \)
- \( 3 + 7 = 10 \)
- \( 10 - 7 = 3 \)
- \( 31 - 18 = 13 \)
- \( 21 - 13 = 8 \)
- \( 27 - 15 = 12 \)
- \( 15 + 5 = 20 \)
- \( 2 + 8 = 10 \)

#### Row 2:
- \( 11 + 8 = 19 \)
- \( 10 + 12 = 22 \)
- \( 6 + 19 = 25 \)
- \( 38 - 18 = 20 \)
- \( 15 + 5 = 20 \)
- \( 20 - 13 = 7 \)
- \( 18 + 8 = 26 \)
- \( 9 - 10 = -1 \)
- \( 16 - 14 = 2 \)
- \( 32 - 2 = 30 \)

#### Row 3:
- \( 19 + 2 = 21 \)
- \( 16 + 14 = 30 \)
- \( 12 + 8 = 20 \)
- \( 10 - 9 = 1 \)
- \( 25 - 13 = 12 \)
- \( 25 - 8 = 17 \)
- \( 21 - 15 = 6 \)
- \( 23 - 12 = 11 \)
- \( 14 - 7 = 7 \)
- \( 1 + 2 = 3 \)

#### Row 4:
- \( 5 - 4 = 1 \)
- \( 6 + 19 = 25 \)
- \( 25 - 8 = 17 \)
- \( 10 - 5 = 5 \)
- \( 19 + 17 = 36 \)
- \( 16 - 14 = 2 \)
- \( 18 - 7 = 11 \)
- \( 13 + 12 = 25 \)
- \( 16 + 14 = 30 \)
- \( 15 + 1 = 16 \)

#### Row 5:
- \( 17 + 11 = 28 \)
- \( 25 - 8 = 17 \)
- \( 18 + 10 = 28 \)
- \( 15 + 14 = 29 \)
- \( 27 - 18 = 9 \)
- \( 17 - 11 = 6 \)
- \( 19 + 16 = 35 \)
- \( 32 - 17 = 15 \)
- \( 8 + 4 = 12 \)
- \( 27 - 12 = 15 \)

#### Row 6:
- \( 10 - 2 = 8 \)
- \( 4 - 1 = 3 \)
- \( 11 - 6 = 5 \)
- \( 21 - 3 = 18 \)
- \( 20 + 20 = 40 \)
- \( 16 + 18 = 34 \)
- \( 17 - 10 = 7 \)
- \( 18 + 8 = 26 \)
- \( 12 + 6 = 18 \)

#### Row 7:
- \( 12 + 4 = 16 \)
- \( 11 + 9 = 20 \)
- \( 14 + 6 = 20 \)
- \( 5 + 4 = 9 \)
- \( 27 - 10 = 17 \)
- \( 5 + 20 = 25 \)
- \( 19 + 1 = 20 \)
- \( 24 - 13 = 11 \)
- \( 21 - 3 = 18 \)
- \( 22 - 20 = 2 \)

#### Row 8:
- \( 19 + 8 = 27 \)
- \( 23 - 18 = 5 \)
- \( 16 + 17 = 33 \)
- \( 4 + 11 = 15 \)
- \( 30 - 13 = 17 \)
- \( 34 - 15 = 19 \)
- \( 14 - 2 = 12 \)
- \( 17 - 14 = 3 \)
- \( 3 + 5 = 8 \)
- \( 12 + 1 = 13 \)

#### Row 9:
- \( 13 + 10 = 23 \)
- \( 27 - 18 = 9 \)
- \( 10 + 20 = 30 \)
- \( 5 + 16 = 21 \)
- \( 10 + 17 = 27 \)
- \( 12 + 2 = 14 \)
- \( 5 - 2 = 3 \)
- \( 5 + 18 = 23 \)
- \( 17 + 7 = 24 \)
- \( 16 - 6 = 10 \)

#### Row 10:
- \( 13 - 1 = 12 \)
- \( 20 - 1 = 19 \)
- \( 5 - 1 = 4 \)
- \( 7 + 14 = 21 \)
- \( 21 - 3 = 18 \)
- \( 19 + 13 = 32 \)
- \( 15 - 7 = 8 \)
- \( 20 - 9 = 11 \)
- \( 1 + 18 = 19 \)
- \( 6 + 5 = 11 \)

Final Answer:

\[
\boxed{
\begin{array}{cccccccccc}
18 & 14 & 25 & 10 & 3 & 13 & 8 & 12 & 20 & 10 \\
19 & 22 & 25 & 20 & 20 & 7 & 26 & -1 & 2 & 30 \\
21 & 30 & 20 & 1 & 12 & 17 & 6 & 11 & 7 & 3 \\
1 & 25 & 17 & 5 & 36 & 2 & 11 & 25 & 30 & 16 \\
28 & 17 & 28 & 29 & 9 & 6 & 35 & 15 & 12 & 15 \\
8 & 3 & 5 & 18 & 40 & 34 & 7 & 26 & 18 & \\
16 & 20 & 20 & 9 & 17 & 25 & 20 & 11 & 18 & 2 \\
27 & 5 & 33 & 15 & 17 & 19 & 12 & 3 & 8 & 13 \\
23 & 9 & 30 & 21 & 27 & 14 & 3 & 23 & 24 & 10 \\
12 & 19 & 4 & 21 & 18 & 32 & 8 & 11 & 19 & 11 \\
\end{array}
}
\]