OK, let's do this. We've got 600 and 165 and we're adding them all together.

Step 1: We'll start by adding the digits 0 & 5 in column 1 and get 5.

Step 2: We'll start by adding the digits 0 & 6 in column 2 and get 6.

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

So, 600 + 165 = 765.

