Okay, we are given 202 and 153. Let's add them up step by step.

Step 1: We'll start by adding the digits 2 & 3 in column 1 and get 5.

Step 2: We'll start by adding the digits 0 & 5 in column 2 and get 5.

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

So, 202 + 153 = 355.

