We are presented with 536 and 9003. Let's work out the sum.

Step 1: We'll start by adding the digits 6 & 3 in column 1 and get 9.

Step 2: We'll start by adding the digits 3 & 0 in column 2 and get 3.

Step 3: We'll start by adding the digits 5 & 0 in column 3 and get 5.

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

So, 536 + 9003 = 9539.

