Let's roll up our sleeves and solve this. We have 513 and we're going to multiply it by 3, essentially adding 513 to itself 3 times.
Step 1: 0 + 513 = 513
Step 2: 513 + 513 = 1026
Step 3: 1026 + 513 = 1539

So, 513*3 = 1539