Not to worry, we've got 8156 and 1240. Let's get to adding them!

Step 1: We'll start by adding the digits 6 & 0 in column 1 and get 6.

Step 2: We'll start by adding the digits 5 & 4 in column 2 and get 9.

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

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

So, 8156 + 1240 = 9396.

