OK, let's do this. We've got 7400 and 2289 and we're adding them all together.

Step 1: We'll start by adding the digits 0 & 9 in column 1 and get 9.

Step 2: We'll start by adding the digits 0 & 8 in column 2 and get 8.

Step 3: We'll start by adding the digits 4 & 2 in column 3 and get 6.

Step 4: We'll start by adding the digits 7 & 2 in column 4 and get 9.

So, 7400 + 2289 = 9689.

