Not to worry, we've got 5255020872 and 2665233865. Let's get to adding them!

Step 1: We'll start by adding the digits 2 & 5 in column 1 and get 7.

Step 2: We'll start by adding the digits 7 & 6 in column 2 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 8 & 8 in column 3 and get 17.
We'll write down the last digit 7 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 0 & 3 in column 4 and get 4.

Step 5: We'll start by adding the digits 2 & 3 in column 5 and get 5.

Step 6: We'll start by adding the digits 0 & 2 in column 6 and get 2.

Step 7: We'll start by adding the digits 5 & 5 in column 7 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

Step 8: We'll start by adding the digits 5 & 6 in column 8 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

Step 9: We'll start by adding the digits 2 & 6 in column 9 and get 9.

Step 10: We'll start by adding the digits 5 & 2 in column 10 and get 7.

So, 5255020872 + 2665233865 = 7920254737.

