OK, let's do this. We've got 307 and 7662 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 0 & 6 in column 2 and get 6.

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

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

So, 307 + 7662 = 7969.

