Alright, let's solve this problem step by step. We have 178 and 620 and we're adding them together.

Step 1: We'll start by adding the digits 8 & 0 in column 1 and get 8.

Step 2: We'll start by adding the digits 7 & 2 in column 2 and get 9.

Step 3: We'll start by adding the digits 1 & 6 in column 3 and get 7.

So, 178 + 620 = 798.

