OK, let's do this. We've got 7517 and 222 and we're adding them all together.

Step 1: We'll start by adding the digits 7 & 2 in column 1 and get 9.

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

Step 3: We'll start by adding the digits 5 & 2 in column 3 and get 7.

Step 4: We'll start by adding the digits 7 & 0 in column 4 and get 7.

So, 7517 + 222 = 7739.

