We have numbers 602 and 4307. Let's start adding them together.

Step 1: We'll start by adding the digits 2 & 7 in column 1 and get 9.

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

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

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

So, 602 + 4307 = 4909.

