Alright, let's solve this problem step by step. We have 6819 and 4687 and we're adding them together.

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

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

Step 3: We'll start by adding the digits 8 & 6 in column 3 and get 15.
We'll write down the last digit 5 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 6 & 4 in column 4 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

So, 6819 + 4687 = 11506.

