OK, let's work through this together. We're starting with 916 and we're going to multiply it by 91, which means we add 916 to itself 91 times.
Step 1: 0 + 916 = 916
Step 2: 916 + 916 = 1832
Step 3: 1832 + 916 = 2748
Step 4: 2748 + 916 = 3664
Step 5: 3664 + 916 = 4580
Step 6: 4580 + 916 = 5496
Step 7: 5496 + 916 = 6412
Step 8: 6412 + 916 = 7328
Step 9: 7328 + 916 = 8244
Step 10: 8244 + 916 = 9160
Step 11: 9160 + 916 = 10076
Step 12: 10076 + 916 = 10992
Step 13: 10992 + 916 = 11908
Step 14: 11908 + 916 = 12824
Step 15: 12824 + 916 = 13740
Step 16: 13740 + 916 = 14656
Step 17: 14656 + 916 = 15572
Step 18: 15572 + 916 = 16488
Step 19: 16488 + 916 = 17404
Step 20: 17404 + 916 = 18320
Step 21: 18320 + 916 = 19236
Step 22: 19236 + 916 = 20152
Step 23: 20152 + 916 = 21068
Step 24: 21068 + 916 = 21984
Step 25: 21984 + 916 = 22900
Step 26: 22900 + 916 = 23816
Step 27: 23816 + 916 = 24732
Step 28: 24732 + 916 = 25648
Step 29: 25648 + 916 = 26564
Step 30: 26564 + 916 = 27480
Step 31: 27480 + 916 = 28396
Step 32: 28396 + 916 = 29312
Step 33: 29312 + 916 = 30228
Step 34: 30228 + 916 = 31144
Step 35: 31144 + 916 = 32060
Step 36: 32060 + 916 = 32976
Step 37: 32976 + 916 = 33892
Step 38: 33892 + 916 = 34808
Step 39: 34808 + 916 = 35724
Step 40: 35724 + 916 = 36640
Step 41: 36640 + 916 = 37556
Step 42: 37556 + 916 = 38472
Step 43: 38472 + 916 = 39388
Step 44: 39388 + 916 = 40304
Step 45: 40304 + 916 = 41220
Step 46: 41220 + 916 = 42136
Step 47: 42136 + 916 = 43052
Step 48: 43052 + 916 = 43968
Step 49: 43968 + 916 = 44884
Step 50: 44884 + 916 = 45800
Step 51: 45800 + 916 = 46716
Step 52: 46716 + 916 = 47632
Step 53: 47632 + 916 = 48548
Step 54: 48548 + 916 = 49464
Step 55: 49464 + 916 = 50380
Step 56: 50380 + 916 = 51296
Step 57: 51296 + 916 = 52212
Step 58: 52212 + 916 = 53128
Step 59: 53128 + 916 = 54044
Step 60: 54044 + 916 = 54960
Step 61: 54960 + 916 = 55876
Step 62: 55876 + 916 = 56792
Step 63: 56792 + 916 = 57708
Step 64: 57708 + 916 = 58624
Step 65: 58624 + 916 = 59540
Step 66: 59540 + 916 = 60456
Step 67: 60456 + 916 = 61372
Step 68: 61372 + 916 = 62288
Step 69: 62288 + 916 = 63204
Step 70: 63204 + 916 = 64120
Step 71: 64120 + 916 = 65036
Step 72: 65036 + 916 = 65952
Step 73: 65952 + 916 = 66868
Step 74: 66868 + 916 = 67784
Step 75: 67784 + 916 = 68700
Step 76: 68700 + 916 = 69616
Step 77: 69616 + 916 = 70532
Step 78: 70532 + 916 = 71448
Step 79: 71448 + 916 = 72364
Step 80: 72364 + 916 = 73280
Step 81: 73280 + 916 = 74196
Step 82: 74196 + 916 = 75112
Step 83: 75112 + 916 = 76028
Step 84: 76028 + 916 = 76944
Step 85: 76944 + 916 = 77860
Step 86: 77860 + 916 = 78776
Step 87: 78776 + 916 = 79692
Step 88: 79692 + 916 = 80608
Step 89: 80608 + 916 = 81524
Step 90: 81524 + 916 = 82440
Step 91: 82440 + 916 = 83356

So, 916*91 = 83356