OK, let's do this. We've got 7516 and 471 and we're adding them all together.

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

Step 2: We'll start by adding the digits 1 & 7 in column 2 and get 8.

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 7 & 0 in column 4 and get 7.

So, 7516 + 471 = 7987.

