Okay, we are given 4403 and 5241. Let's add them up step by step.

Step 1: We'll start by adding the digits 3 & 1 in column 1 and get 4.

Step 2: We'll start by adding the digits 0 & 4 in column 2 and get 4.

Step 3: We'll start by adding the digits 4 & 2 in column 3 and get 6.

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

So, 4403 + 5241 = 9644.

