No problem, let's work through this together. We're starting with 87 and 17 and adding them all up.

Step 1: We'll start by adding the digits 7 & 7 in column 1 and get 14.
We'll write down the last digit 4 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 8 & 1 in column 2 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

So, 87 + 17 = 104.

