No problem, let's work through this together. We're starting with 4085 and 3173 and adding them all up.

Step 1: We'll start by adding the digits 5 & 3 in column 1 and get 8.

Step 2: We'll start by adding the digits 8 & 7 in column 2 and get 15.
We'll write down the last digit 5 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 0 & 1 in column 3 and get 2.

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

So, 4085 + 3173 = 7258.

