OK, let's do this. We've got 2510 and 2481 and we're adding them all together.

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

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

Step 3: We'll start by adding the digits 5 & 4 in column 3 and get 9.

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

So, 2510 + 2481 = 4991.

