We are presented with 13 and 5645. Let's work out the sum.

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 & 4 in column 2 and get 5.

Step 3: We'll start by adding the digits 0 & 6 in column 3 and get 6.

Step 4: We'll start by adding the digits 0 & 5 in column 4 and get 5.

So, 13 + 5645 = 5658.

