Not to worry, we've got 7733 and 9900. Let's get to adding them!

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 3 & 0 in column 2 and get 3.

Step 3: We'll start by adding the digits 7 & 9 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 7 & 9 in column 4 and get 17.
We'll write down the last digit 7 and carry the 1 to the next column.

So, 7733 + 9900 = 17633.

