Alright, let's solve this math problem step by step. First, we have the number 429. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 12. So, we're going to take the number 429 and add it to itself 12 times.
Step 1: 0 + 429 = 429
Step 2: 429 + 429 = 858
Step 3: 858 + 429 = 1287
Step 4: 1287 + 429 = 1716
Step 5: 1716 + 429 = 2145
Step 6: 2145 + 429 = 2574
Step 7: 2574 + 429 = 3003
Step 8: 3003 + 429 = 3432
Step 9: 3432 + 429 = 3861
Step 10: 3861 + 429 = 4290
Step 11: 4290 + 429 = 4719
Step 12: 4719 + 429 = 5148

So, 429*12 = 5148