Let's roll up our sleeves and solve this. We have 454 and we're going to multiply it by 12, essentially adding 454 to itself 12 times.
Step 1: 0 + 454 = 454
Step 2: 454 + 454 = 908
Step 3: 908 + 454 = 1362
Step 4: 1362 + 454 = 1816
Step 5: 1816 + 454 = 2270
Step 6: 2270 + 454 = 2724
Step 7: 2724 + 454 = 3178
Step 8: 3178 + 454 = 3632
Step 9: 3632 + 454 = 4086
Step 10: 4086 + 454 = 4540
Step 11: 4540 + 454 = 4994
Step 12: 4994 + 454 = 5448

So, 454*12 = 5448