We are presented with 4203 and 515. Let's work out the sum.

Step 1: We'll start by adding the digits 3 & 5 in column 1 and get 8.

Step 2: We'll start by adding the digits 0 & 1 in column 2 and get 1.

Step 3: We'll start by adding the digits 2 & 5 in column 3 and get 7.

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

So, 4203 + 515 = 4718.

