Here we go! We're going to add 1015 and 8940 together.

Step 1: We'll start by adding the digits 5 & 0 in column 1 and get 5.

Step 2: We'll start by adding the digits 1 & 4 in column 2 and get 5.

Step 3: We'll start by adding the digits 0 & 9 in column 3 and get 9.

Step 4: We'll start by adding the digits 1 & 8 in column 4 and get 9.

So, 1015 + 8940 = 9955.

