Here we go! We're going to add 1001 and 8394 together.

Step 1: We'll start by adding the digits 1 & 4 in column 1 and get 5.

Step 2: We'll start by adding the digits 0 & 9 in column 2 and get 9.

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

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

So, 1001 + 8394 = 9395.

