Let's solve this addition problem. We have 543 and 9880, and we need to add them together.

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 4 & 8 in column 2 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 5 & 8 in column 3 and get 14.
We'll write down the last digit 4 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 0 & 9 in column 4 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

So, 543 + 9880 = 10423.

