OK, let's do this. We've got 6105 and 3116 and we're adding them all together.

Step 1: We'll start by adding the digits 5 & 6 in column 1 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 0 & 1 in column 2 and get 2.

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

Step 4: We'll start by adding the digits 6 & 3 in column 4 and get 9.

So, 6105 + 3116 = 9221.

