OK, let's do this. We've got 2281 and 6710 and we're adding them all together.

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

Step 2: We'll start by adding the digits 8 & 1 in column 2 and get 9.

Step 3: We'll start by adding the digits 2 & 7 in column 3 and get 9.

Step 4: We'll start by adding the digits 2 & 6 in column 4 and get 8.

So, 2281 + 6710 = 8991.

