No problem, let's work through this together. We're starting with 7845 and 7231 and adding them all up.

Step 1: We'll start by adding the digits 5 & 1 in column 1 and get 6.

Step 2: We'll start by adding the digits 4 & 3 in column 2 and get 7.

Step 3: We'll start by adding the digits 8 & 2 in column 3 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 7 & 7 in column 4 and get 15.
We'll write down the last digit 5 and carry the 1 to the next column.

So, 7845 + 7231 = 15076.

