Let's solve this addition problem. We have 3104 and 4873, and we need to add them together.

Step 1: We'll start by adding the digits 4 & 3 in column 1 and get 7.

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

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 3 & 4 in column 4 and get 7.

So, 3104 + 4873 = 7977.

