Let's solve this addition problem. We have 301 and 619, and we need to add them together.

Step 1: We'll start by adding the digits 1 & 9 in column 1 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 0 & 1 in column 2 and get 2.

Step 3: We'll start by adding the digits 3 & 6 in column 3 and get 9.

So, 301 + 619 = 920.

