OK, let's work through this together. We're starting with 402 and we're going to multiply it by 12, which means we add 402 to itself 12 times.
Step 1: 0 + 402 = 402
Step 2: 402 + 402 = 804
Step 3: 804 + 402 = 1206
Step 4: 1206 + 402 = 1608
Step 5: 1608 + 402 = 2010
Step 6: 2010 + 402 = 2412
Step 7: 2412 + 402 = 2814
Step 8: 2814 + 402 = 3216
Step 9: 3216 + 402 = 3618
Step 10: 3618 + 402 = 4020
Step 11: 4020 + 402 = 4422
Step 12: 4422 + 402 = 4824

So, 402*12 = 4824