Okay, we are tasked with adding 2402 and 7507. Let's begin!

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 4 & 5 in column 3 and get 9.

Step 4: We'll start by adding the digits 2 & 7 in column 4 and get 9.

So, 2402 + 7507 = 9909.

