Alright, let's solve this problem step by step. We have 770 and 8007 and we're adding them together.

Step 1: We'll start by adding the digits 0 & 7 in column 1 and get 7.

Step 2: We'll start by adding the digits 7 & 0 in column 2 and get 7.

Step 3: We'll start by adding the digits 7 & 0 in column 3 and get 7.

Step 4: We'll start by adding the digits 0 & 8 in column 4 and get 8.

So, 770 + 8007 = 8777.

