OK, let's do this. We've got 63 and 9933 and we're adding them all together.

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

Step 2: We'll start by adding the digits 6 & 3 in column 2 and get 9.

Step 3: We'll start by adding the digits 0 & 9 in column 3 and get 9.

Step 4: We'll start by adding the digits 0 & 9 in column 4 and get 9.

So, 63 + 9933 = 9996.

