OK, let's do this. We've got 5900 and 3713 and we're adding them all together.

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

Step 2: We'll start by adding the digits 0 & 1 in column 2 and get 1.

Step 3: We'll start by adding the digits 9 & 7 in column 3 and get 16.
We'll write down the last digit 6 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 5 & 3 in column 4 and get 9.

So, 5900 + 3713 = 9613.

