Okay, we are tasked with adding 5478 and 4000. Let's begin!

Step 1: We'll start by adding the digits 8 & 0 in column 1 and get 8.

Step 2: We'll start by adding the digits 7 & 0 in column 2 and get 7.

Step 3: We'll start by adding the digits 4 & 0 in column 3 and get 4.

Step 4: We'll start by adding the digits 5 & 4 in column 4 and get 9.

So, 5478 + 4000 = 9478.

