Let's break this down. We're going to add 6174 and 4245 together.

Step 1: We'll start by adding the digits 4 & 5 in column 1 and get 9.

Step 2: We'll start by adding the digits 7 & 4 in column 2 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 1 & 2 in column 3 and get 4.

Step 4: We'll start by adding the digits 6 & 4 in column 4 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

So, 6174 + 4245 = 10419.

