Sure thing, let's get straight to it. We start with 813 and we're going to multiply it by 109, which means adding 813 to itself 109 times.
Step 1: 0 + 813 = 813
Step 2: 813 + 813 = 1626
Step 3: 1626 + 813 = 2439
Step 4: 2439 + 813 = 3252
Step 5: 3252 + 813 = 4065
Step 6: 4065 + 813 = 4878
Step 7: 4878 + 813 = 5691
Step 8: 5691 + 813 = 6504
Step 9: 6504 + 813 = 7317
Step 10: 7317 + 813 = 8130
Step 11: 8130 + 813 = 8943
Step 12: 8943 + 813 = 9756
Step 13: 9756 + 813 = 10569
Step 14: 10569 + 813 = 11382
Step 15: 11382 + 813 = 12195
Step 16: 12195 + 813 = 13008
Step 17: 13008 + 813 = 13821
Step 18: 13821 + 813 = 14634
Step 19: 14634 + 813 = 15447
Step 20: 15447 + 813 = 16260
Step 21: 16260 + 813 = 17073
Step 22: 17073 + 813 = 17886
Step 23: 17886 + 813 = 18699
Step 24: 18699 + 813 = 19512
Step 25: 19512 + 813 = 20325
Step 26: 20325 + 813 = 21138
Step 27: 21138 + 813 = 21951
Step 28: 21951 + 813 = 22764
Step 29: 22764 + 813 = 23577
Step 30: 23577 + 813 = 24390
Step 31: 24390 + 813 = 25203
Step 32: 25203 + 813 = 26016
Step 33: 26016 + 813 = 26829
Step 34: 26829 + 813 = 27642
Step 35: 27642 + 813 = 28455
Step 36: 28455 + 813 = 29268
Step 37: 29268 + 813 = 30081
Step 38: 30081 + 813 = 30894
Step 39: 30894 + 813 = 31707
Step 40: 31707 + 813 = 32520
Step 41: 32520 + 813 = 33333
Step 42: 33333 + 813 = 34146
Step 43: 34146 + 813 = 34959
Step 44: 34959 + 813 = 35772
Step 45: 35772 + 813 = 36585
Step 46: 36585 + 813 = 37398
Step 47: 37398 + 813 = 38211
Step 48: 38211 + 813 = 39024
Step 49: 39024 + 813 = 39837
Step 50: 39837 + 813 = 40650
Step 51: 40650 + 813 = 41463
Step 52: 41463 + 813 = 42276
Step 53: 42276 + 813 = 43089
Step 54: 43089 + 813 = 43902
Step 55: 43902 + 813 = 44715
Step 56: 44715 + 813 = 45528
Step 57: 45528 + 813 = 46341
Step 58: 46341 + 813 = 47154
Step 59: 47154 + 813 = 47967
Step 60: 47967 + 813 = 48780
Step 61: 48780 + 813 = 49593
Step 62: 49593 + 813 = 50406
Step 63: 50406 + 813 = 51219
Step 64: 51219 + 813 = 52032
Step 65: 52032 + 813 = 52845
Step 66: 52845 + 813 = 53658
Step 67: 53658 + 813 = 54471
Step 68: 54471 + 813 = 55284
Step 69: 55284 + 813 = 56097
Step 70: 56097 + 813 = 56910
Step 71: 56910 + 813 = 57723
Step 72: 57723 + 813 = 58536
Step 73: 58536 + 813 = 59349
Step 74: 59349 + 813 = 60162
Step 75: 60162 + 813 = 60975
Step 76: 60975 + 813 = 61788
Step 77: 61788 + 813 = 62601
Step 78: 62601 + 813 = 63414
Step 79: 63414 + 813 = 64227
Step 80: 64227 + 813 = 65040
Step 81: 65040 + 813 = 65853
Step 82: 65853 + 813 = 66666
Step 83: 66666 + 813 = 67479
Step 84: 67479 + 813 = 68292
Step 85: 68292 + 813 = 69105
Step 86: 69105 + 813 = 69918
Step 87: 69918 + 813 = 70731
Step 88: 70731 + 813 = 71544
Step 89: 71544 + 813 = 72357
Step 90: 72357 + 813 = 73170
Step 91: 73170 + 813 = 73983
Step 92: 73983 + 813 = 74796
Step 93: 74796 + 813 = 75609
Step 94: 75609 + 813 = 76422
Step 95: 76422 + 813 = 77235
Step 96: 77235 + 813 = 78048
Step 97: 78048 + 813 = 78861
Step 98: 78861 + 813 = 79674
Step 99: 79674 + 813 = 80487
Step 100: 80487 + 813 = 81300
Step 101: 81300 + 813 = 82113
Step 102: 82113 + 813 = 82926
Step 103: 82926 + 813 = 83739
Step 104: 83739 + 813 = 84552
Step 105: 84552 + 813 = 85365
Step 106: 85365 + 813 = 86178
Step 107: 86178 + 813 = 86991
Step 108: 86991 + 813 = 87804
Step 109: 87804 + 813 = 88617

So, 813*109 = 88617