Solve Four-Digit Addition: 5421 + 1657 Using Column Method

To solve the problem of adding 5421 and 1657 using vertical addition, we will proceed through the following steps:

Step 1: Align the numbers vertically according to their place values:

$\begin{aligned} &5421 \\ + &1657 \\ \end{aligned}$

Step 2: Begin addition from the rightmost digit (units place):

• Units place: $1 + 7 = 8$. Write 8 in the units place.
• Tens place: $2 + 5 = 7$. Write 7 in the tens place.
• Hundreds place: $4 + 6 = 10$. Write 0 in the hundreds place and carry over 1 to the thousands place.
• Thousands place: $5 + 1 = 6$, plus the carried over 1 gives $6 + 1 = 7$. Write 7 in the thousands place.

Step 3: Write down the final result underneath the drawn line:

$\begin{aligned} &\underline{7078} \end{aligned}$

Therefore, the sum of 5421 and 1657 is $\textbf{7078}$.