Let's break this down. We're going to add 1857 and 8000 together.

Step 1: We'll start by adding the digits 7 & 0 in column 1 and get 7.

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 & 0 in column 3 and get 8.

Step 4: We'll start by adding the digits 1 & 8 in column 4 and get 9.

So, 1857 + 8000 = 9857.

