Not to worry, we've got 112 and 631. Let's get to adding them!

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

Step 2: We'll start by adding the digits 1 & 3 in column 2 and get 4.

Step 3: We'll start by adding the digits 1 & 6 in column 3 and get 7.

So, 112 + 631 = 743.

