Here we go! We're going to add 5858 and 7801 together.

Step 1: We'll start by adding the digits 8 & 1 in column 1 and get 9.

Step 2: We'll start by adding the digits 5 & 0 in column 2 and get 5.

Step 3: We'll start by adding the digits 8 & 8 in column 3 and get 16.
We'll write down the last digit 6 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 5 & 7 in column 4 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

So, 5858 + 7801 = 13659.

