Okay, we are tasked with adding 2429 and 5556. Let's begin!

Step 1: We'll start by adding the digits 9 & 6 in column 1 and get 15.
We'll write down the last digit 5 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 2 & 5 in column 2 and get 8.

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

Step 4: We'll start by adding the digits 2 & 5 in column 4 and get 7.

So, 2429 + 5556 = 7985.

