Not to worry, we've got 6511 and 4013. Let's get to adding them!

Step 1: We'll start by adding the digits 1 & 3 in column 1 and get 4.

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

Step 3: We'll start by adding the digits 5 & 0 in column 3 and get 5.

Step 4: We'll start by adding the digits 6 & 4 in column 4 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

So, 6511 + 4013 = 10524.

