We have numbers 128 and 448. Let's start adding them together.

Step 1: We'll start by adding the digits 8 & 8 in column 1 and get 16.
We'll write down the last digit 6 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 2 & 4 in column 2 and get 7.

Step 3: We'll start by adding the digits 1 & 4 in column 3 and get 5.

So, 128 + 448 = 576.

