Okay, we are given 313 and 1155. Let's add them up step by step.

Step 1: We'll start by adding the digits 3 & 5 in column 1 and get 8.

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 3 & 1 in column 3 and get 4.

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

So, 313 + 1155 = 1468.

