OK, let's crack this. We're given 429 and our task is to multiply it by 9. Essentially, we'll be adding 429 to itself 9 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

So, 429*9 = 3861