OK, let's do this. We've got 8257 and 1211 and we're adding them all together.

Step 1: We'll start by adding the digits 7 & 1 in column 1 and get 8.

Step 2: We'll start by adding the digits 5 & 1 in column 2 and get 6.

Step 3: We'll start by adding the digits 2 & 2 in column 3 and get 4.

Step 4: We'll start by adding the digits 8 & 1 in column 4 and get 9.

So, 8257 + 1211 = 9468.

