No problem, let's work through this together. We're starting with 1390 and 7171 and adding them all up.

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

Step 2: We'll start by adding the digits 9 & 7 in column 2 and get 16.
We'll write down the last digit 6 and carry the 1 to the next column.

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

Step 4: We'll start by adding the digits 1 & 7 in column 4 and get 8.

So, 1390 + 7171 = 8561.

