Okay, we are tasked with adding 3800 and 7561. Let's begin!

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 0 & 6 in column 2 and get 6.

Step 3: We'll start by adding the digits 8 & 5 in column 3 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 3 & 7 in column 4 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

So, 3800 + 7561 = 11361.

