Let's break this down. We're going to add 2420 and 5450 together.

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

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

Step 3: We'll start by adding the digits 4 & 4 in column 3 and get 8.

Step 4: We'll start by adding the digits 2 & 5 in column 4 and get 7.

So, 2420 + 5450 = 7870.

