We have numbers 4021 and 1365. Let's start adding them together.

Step 1: We'll start by adding the digits 1 & 5 in column 1 and get 6.

Step 2: We'll start by adding the digits 2 & 6 in column 2 and get 8.

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

Step 4: We'll start by adding the digits 4 & 1 in column 4 and get 5.

So, 4021 + 1365 = 5386.

