Let's break this down. We're going to add 1163 and 5715 together.

Step 1: We'll start by adding the digits 3 & 5 in column 1 and get 8.

Step 2: We'll start by adding the digits 6 & 1 in column 2 and get 7.

Step 3: We'll start by adding the digits 1 & 7 in column 3 and get 8.

Step 4: We'll start by adding the digits 1 & 5 in column 4 and get 6.

So, 1163 + 5715 = 6878.

