Let's break this down. We're going to add 10 and 254 together.

Step 1: We'll start by adding the digits 0 & 4 in column 1 and get 4.

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 0 & 2 in column 3 and get 2.

So, 10 + 254 = 264.

