We have numbers 948 and 3401. Let's start adding them together.

Step 1: We'll start by adding the digits 8 & 1 in column 1 and get 9.

Step 2: We'll start by adding the digits 4 & 0 in column 2 and get 4.

Step 3: We'll start by adding the digits 9 & 4 in column 3 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 0 & 3 in column 4 and get 4.

So, 948 + 3401 = 4349.

