Let's get this math done. We have 451 and we're going to multiply it by 3. This is the same as taking 451 and adding it to itself 3 times.
Step 1: 0 + 451 = 451
Step 2: 451 + 451 = 902
Step 3: 902 + 451 = 1353

So, 451*3 = 1353