OK, let's do this. We've got 4602 and 4101 and we're adding them all together.

Step 1: We'll start by adding the digits 2 & 1 in column 1 and get 3.

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

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

Step 4: We'll start by adding the digits 4 & 4 in column 4 and get 8.

So, 4602 + 4101 = 8703.

