OK, let's work through this together. We're starting with 348 and we're going to multiply it by 12, which means we add 348 to itself 12 times.
Step 1: 0 + 348 = 348
Step 2: 348 + 348 = 696
Step 3: 696 + 348 = 1044
Step 4: 1044 + 348 = 1392
Step 5: 1392 + 348 = 1740
Step 6: 1740 + 348 = 2088
Step 7: 2088 + 348 = 2436
Step 8: 2436 + 348 = 2784
Step 9: 2784 + 348 = 3132
Step 10: 3132 + 348 = 3480
Step 11: 3480 + 348 = 3828
Step 12: 3828 + 348 = 4176

So, 348*12 = 4176