Alright, let's solve this math problem step by step. First, we have the number 603. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 6. So, we're going to take the number 603 and add it to itself 6 times.
Step 1: 0 + 603 = 603
Step 2: 603 + 603 = 1206
Step 3: 1206 + 603 = 1809
Step 4: 1809 + 603 = 2412
Step 5: 2412 + 603 = 3015
Step 6: 3015 + 603 = 3618

So, 603*6 = 3618