We've got two numbers: 312 and 9667. Let's find their sum.

Step 1: We'll start by adding the digits 2 & 7 in column 1 and get 9.

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

Step 3: We'll start by adding the digits 3 & 6 in column 3 and get 9.

Step 4: We'll start by adding the digits 0 & 9 in column 4 and get 9.

So, 312 + 9667 = 9979.

