No problem, let's work through this together. We're starting with 616 and 207 and adding them all up.

Step 1: We'll start by adding the digits 6 & 7 in column 1 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

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

Step 3: We'll start by adding the digits 6 & 2 in column 3 and get 8.

So, 616 + 207 = 823.

