OK, let's work through this together. We're starting with 426 and we're going to multiply it by 30, which means we add 426 to itself 30 times.
Step 1: 0 + 426 = 426
Step 2: 426 + 426 = 852
Step 3: 852 + 426 = 1278
Step 4: 1278 + 426 = 1704
Step 5: 1704 + 426 = 2130
Step 6: 2130 + 426 = 2556
Step 7: 2556 + 426 = 2982
Step 8: 2982 + 426 = 3408
Step 9: 3408 + 426 = 3834
Step 10: 3834 + 426 = 4260
Step 11: 4260 + 426 = 4686
Step 12: 4686 + 426 = 5112
Step 13: 5112 + 426 = 5538
Step 14: 5538 + 426 = 5964
Step 15: 5964 + 426 = 6390
Step 16: 6390 + 426 = 6816
Step 17: 6816 + 426 = 7242
Step 18: 7242 + 426 = 7668
Step 19: 7668 + 426 = 8094
Step 20: 8094 + 426 = 8520
Step 21: 8520 + 426 = 8946
Step 22: 8946 + 426 = 9372
Step 23: 9372 + 426 = 9798
Step 24: 9798 + 426 = 10224
Step 25: 10224 + 426 = 10650
Step 26: 10650 + 426 = 11076
Step 27: 11076 + 426 = 11502
Step 28: 11502 + 426 = 11928
Step 29: 11928 + 426 = 12354
Step 30: 12354 + 426 = 12780

So, 426*30 = 12780