Here we go! We're going to add 1426 and 8729 together.

Step 1: We'll start by adding the digits 6 & 9 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 & 2 in column 2 and get 5.

Step 3: We'll start by adding the digits 4 & 7 in column 3 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 1 & 8 in column 4 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

So, 1426 + 8729 = 10155.

