FREE Printable 3rd Grade Math Minutes Worksheets pdf - Free Printable

Problem Explanation:

The worksheet is designed to teach the Associative Property of Addition, which states that when adding three or more numbers, the way in which the numbers are grouped does not affect the sum. For example:

\[
(a + b) + c = a + (b + c)
\]

The task involves matching the given addition problems with their equivalent forms and calculating the total sum.

Steps to Solve:

1. Calculate the total for each addition problem.
2. Match the total with one of the provided "10 + ?" expressions.
3. Write the total number in the final column.

#### Given Problems:
1. \( 3 + 7 + 4 \)
2. \( 1 + 9 + 3 \)
3. \( 2 + 8 + 9 \)
4. \( 4 + 6 + 2 \)
5. \( 5 + 5 + 6 \)

#### Provided Matching Expressions:
- \( 10 + 9 \)
- \( 10 + 3 \)
- \( 10 + 2 \)
- \( 10 + 6 \)
- \( 10 + 4 \)

---

Solution:

#### 1. \( 3 + 7 + 4 \)
- First, calculate the total:
\[
3 + 7 + 4 = 10 + 4 = 14
\]
- Match with \( 10 + 4 \).
- Total: \( 14 \).

#### 2. \( 1 + 9 + 3 \)
- First, calculate the total:
\[
1 + 9 + 3 = 10 + 3 = 13
\]
- Match with \( 10 + 3 \).
- Total: \( 13 \).

#### 3. \( 2 + 8 + 9 \)
- First, calculate the total:
\[
2 + 8 + 9 = 10 + 9 = 19
\]
- Match with \( 10 + 9 \).
- Total: \( 19 \).

#### 4. \( 4 + 6 + 2 \)
- First, calculate the total:
\[
4 + 6 + 2 = 10 + 2 = 12
\]
- Match with \( 10 + 2 \).
- Total: \( 12 \).

#### 5. \( 5 + 5 + 6 \)
- First, calculate the total:
\[
5 + 5 + 6 = 10 + 6 = 16
\]
- Match with \( 10 + 6 \).
- Total: \( 16 \).

---

Final Answer:

\[
\begin{aligned}
1. & \quad 3 + 7 + 4 = 10 + 4 = 14 \\
2. & \quad 1 + 9 + 3 = 10 + 3 = 13 \\
3. & \quad 2 + 8 + 9 = 10 + 9 = 19 \\
4. & \quad 4 + 6 + 2 = 10 + 2 = 12 \\
5. & \quad 5 + 5 + 6 = 10 + 6 = 16 \\
\end{aligned}
\]

\boxed{
\begin{array}{lll}
3 + 7 + 4 = & 10 + 4 & = 14 \\
1 + 9 + 3 = & 10 + 3 & = 13 \\
2 + 8 + 9 = & 10 + 9 & = 19 \\
4 + 6 + 2 = & 10 + 2 & = 12 \\
5 + 5 + 6 = & 10 + 6 & = 16 \\
\end{array}
}