Here we go! We're going to add 9405 and 570 together.

Step 1: We'll start by adding the digits 5 & 0 in column 1 and get 5.

Step 2: We'll start by adding the digits 0 & 7 in column 2 and get 7.

Step 3: We'll start by adding the digits 4 & 5 in column 3 and get 9.

Step 4: We'll start by adding the digits 9 & 0 in column 4 and get 9.

So, 9405 + 570 = 9975.

