We are presented with 3243 and 5100. Let's work out the sum.

Step 1: We'll start by adding the digits 3 & 0 in column 1 and get 3.

Step 2: We'll start by adding the digits 4 & 0 in column 2 and get 4.

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

Step 4: We'll start by adding the digits 3 & 5 in column 4 and get 8.

So, 3243 + 5100 = 8343.

