Alright, let's solve this problem step by step. We have 4103 and 3861 and we're adding them together.

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 & 6 in column 2 and get 6.

Step 3: We'll start by adding the digits 1 & 8 in column 3 and get 9.

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

So, 4103 + 3861 = 7964.

