Okay, we are given 2112 and 9661. Let's add them up step by step.

Step 1: We'll start by adding the digits 2 & 1 in column 1 and get 3.

Step 2: We'll start by adding the digits 1 & 6 in column 2 and get 7.

Step 3: We'll start by adding the digits 1 & 6 in column 3 and get 7.

Step 4: We'll start by adding the digits 2 & 9 in column 4 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

So, 2112 + 9661 = 11773.

