OK, let's do this. We've got 8694 and 1105 and we're adding them all together.

Step 1: We'll start by adding the digits 4 & 5 in column 1 and get 9.

Step 2: We'll start by adding the digits 9 & 0 in column 2 and get 9.

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

Step 4: We'll start by adding the digits 8 & 1 in column 4 and get 9.

So, 8694 + 1105 = 9799.

