We are presented with 312 and 4174. Let's work out the sum.

Step 1: We'll start by adding the digits 2 & 4 in column 1 and get 6.

Step 2: We'll start by adding the digits 1 & 7 in column 2 and get 8.

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 & 4 in column 4 and get 4.

So, 312 + 4174 = 4486.

