We have numbers 4201 and 3311. Let's start adding them together.

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

Step 2: We'll start by adding the digits 0 & 1 in column 2 and get 1.

Step 3: We'll start by adding the digits 2 & 3 in column 3 and get 5.

Step 4: We'll start by adding the digits 4 & 3 in column 4 and get 7.

So, 4201 + 3311 = 7512.

