Let's break this down. We're going to add 9711 and 3358 together.

Step 1: We'll start by adding the digits 1 & 8 in column 1 and get 9.

Step 2: We'll start by adding the digits 1 & 5 in column 2 and get 6.

Step 3: We'll start by adding the digits 7 & 3 in column 3 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 9 & 3 in column 4 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

So, 9711 + 3358 = 13069.

