Let's get this math done. We have 517 and we're going to multiply it by 3. This is the same as taking 517 and adding it to itself 3 times.
Step 1: 0 + 517 = 517
Step 2: 517 + 517 = 1034
Step 3: 1034 + 517 = 1551

So, 517*3 = 1551