Alright, let's solve this problem step by step. We have 1074 and 7860 and we're adding them together.

Step 1: We'll start by adding the digits 4 & 0 in column 1 and get 4.

Step 2: We'll start by adding the digits 7 & 6 in column 2 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 0 & 8 in column 3 and get 9.

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

So, 1074 + 7860 = 8934.

