Let's get this math done. We have 604 and 745 and we're going to add them all 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 0 & 4 in column 2 and get 4.

Step 3: We'll start by adding the digits 6 & 7 in column 3 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

So, 604 + 745 = 1349.

