Alright, let's solve this math problem step by step. First, we have the number 513. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 15. So, we're going to take the number 513 and add it to itself 15 times.
Step 1: 0 + 513 = 513
Step 2: 513 + 513 = 1026
Step 3: 1026 + 513 = 1539
Step 4: 1539 + 513 = 2052
Step 5: 2052 + 513 = 2565
Step 6: 2565 + 513 = 3078
Step 7: 3078 + 513 = 3591
Step 8: 3591 + 513 = 4104
Step 9: 4104 + 513 = 4617
Step 10: 4617 + 513 = 5130
Step 11: 5130 + 513 = 5643
Step 12: 5643 + 513 = 6156
Step 13: 6156 + 513 = 6669
Step 14: 6669 + 513 = 7182
Step 15: 7182 + 513 = 7695

So, 513*15 = 7695