Here we go! We're going to add 9108 and 5900 together.

Step 1: We'll start by adding the digits 8 & 0 in column 1 and get 8.

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

Step 3: We'll start by adding the digits 1 & 9 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 & 5 in column 4 and get 15.
We'll write down the last digit 5 and carry the 1 to the next column.

So, 9108 + 5900 = 15008.

