Here we go! We're going to add 812 and 3150 together.

Step 1: We'll start by adding the digits 2 & 0 in column 1 and get 2.

Step 2: We'll start by adding the digits 1 & 5 in column 2 and get 6.

Step 3: We'll start by adding the digits 8 & 1 in column 3 and get 9.

Step 4: We'll start by adding the digits 0 & 3 in column 4 and get 3.

So, 812 + 3150 = 3962.

