Let's break this down. We're going to add 3733 and 261 together.

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

Step 2: We'll start by adding the digits 3 & 6 in column 2 and get 9.

Step 3: We'll start by adding the digits 7 & 2 in column 3 and get 9.

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

So, 3733 + 261 = 3994.

