We are presented with 9923 and 9211. Let's work out the sum.

Step 1: We'll start by adding the digits 3 & 1 in column 1 and get 4.

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

Step 3: We'll start by adding the digits 9 & 2 in column 3 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 9 & 9 in column 4 and get 19.
We'll write down the last digit 9 and carry the 1 to the next column.

So, 9923 + 9211 = 19134.

