Calculate the Sum: 7831 + 673 in Vertical Format

To solve this problem, we'll follow these steps:

• Step 1: Align the numbers by their place values:

$\begin{aligned} &7831 \\ +& \\ &~~673 \\ &\underline{\phantom{776}} & \\ \end{aligned}$

• Step 2: Add the digits in each column, starting from the right (units) column.

The unit's column: $1 + 3 = 4$. Write 4 under the units column.

• Step 3: Move to the ten's column.

Add: $3 + 7 = 10$. Write 0 under the tens and carry 1 to the hundreds column.

• Step 4: Move to the hundred's column.

Add: $8 + 6 = 14$, and don't forget the carried 1, making it $15$.

Write 5 under the hundreds and carry 1 to the thousands.

• Step 5: Move to the thousand's column.

Add: $7 + 1 = 8$. Don't forget the carried 1, making it $8$.

Write 8 under the thousands.

The sum of the numbers is:

$\begin{aligned} &7831 \\ +& \\ &~~673 \\ &\underline{\phantom{776}} & \\ &8504 \\ \end{aligned}$

Therefore, the sum of 7831 and 673 is $\mathbf{8504}$.

This corresponds to the choice: :

8504