OK, let's crack this. We're given 791 and our task is to multiply it by 153. Essentially, we'll be adding 791 to itself 153 times.
Step 1: 0 + 791 = 791
Step 2: 791 + 791 = 1582
Step 3: 1582 + 791 = 2373
Step 4: 2373 + 791 = 3164
Step 5: 3164 + 791 = 3955
Step 6: 3955 + 791 = 4746
Step 7: 4746 + 791 = 5537
Step 8: 5537 + 791 = 6328
Step 9: 6328 + 791 = 7119
Step 10: 7119 + 791 = 7910
Step 11: 7910 + 791 = 8701
Step 12: 8701 + 791 = 9492
Step 13: 9492 + 791 = 10283
Step 14: 10283 + 791 = 11074
Step 15: 11074 + 791 = 11865
Step 16: 11865 + 791 = 12656
Step 17: 12656 + 791 = 13447
Step 18: 13447 + 791 = 14238
Step 19: 14238 + 791 = 15029
Step 20: 15029 + 791 = 15820
Step 21: 15820 + 791 = 16611
Step 22: 16611 + 791 = 17402
Step 23: 17402 + 791 = 18193
Step 24: 18193 + 791 = 18984
Step 25: 18984 + 791 = 19775
Step 26: 19775 + 791 = 20566
Step 27: 20566 + 791 = 21357
Step 28: 21357 + 791 = 22148
Step 29: 22148 + 791 = 22939
Step 30: 22939 + 791 = 23730
Step 31: 23730 + 791 = 24521
Step 32: 24521 + 791 = 25312
Step 33: 25312 + 791 = 26103
Step 34: 26103 + 791 = 26894
Step 35: 26894 + 791 = 27685
Step 36: 27685 + 791 = 28476
Step 37: 28476 + 791 = 29267
Step 38: 29267 + 791 = 30058
Step 39: 30058 + 791 = 30849
Step 40: 30849 + 791 = 31640
Step 41: 31640 + 791 = 32431
Step 42: 32431 + 791 = 33222
Step 43: 33222 + 791 = 34013
Step 44: 34013 + 791 = 34804
Step 45: 34804 + 791 = 35595
Step 46: 35595 + 791 = 36386
Step 47: 36386 + 791 = 37177
Step 48: 37177 + 791 = 37968
Step 49: 37968 + 791 = 38759
Step 50: 38759 + 791 = 39550
Step 51: 39550 + 791 = 40341
Step 52: 40341 + 791 = 41132
Step 53: 41132 + 791 = 41923
Step 54: 41923 + 791 = 42714
Step 55: 42714 + 791 = 43505
Step 56: 43505 + 791 = 44296
Step 57: 44296 + 791 = 45087
Step 58: 45087 + 791 = 45878
Step 59: 45878 + 791 = 46669
Step 60: 46669 + 791 = 47460
Step 61: 47460 + 791 = 48251
Step 62: 48251 + 791 = 49042
Step 63: 49042 + 791 = 49833
Step 64: 49833 + 791 = 50624
Step 65: 50624 + 791 = 51415
Step 66: 51415 + 791 = 52206
Step 67: 52206 + 791 = 52997
Step 68: 52997 + 791 = 53788
Step 69: 53788 + 791 = 54579
Step 70: 54579 + 791 = 55370
Step 71: 55370 + 791 = 56161
Step 72: 56161 + 791 = 56952
Step 73: 56952 + 791 = 57743
Step 74: 57743 + 791 = 58534
Step 75: 58534 + 791 = 59325
Step 76: 59325 + 791 = 60116
Step 77: 60116 + 791 = 60907
Step 78: 60907 + 791 = 61698
Step 79: 61698 + 791 = 62489
Step 80: 62489 + 791 = 63280
Step 81: 63280 + 791 = 64071
Step 82: 64071 + 791 = 64862
Step 83: 64862 + 791 = 65653
Step 84: 65653 + 791 = 66444
Step 85: 66444 + 791 = 67235
Step 86: 67235 + 791 = 68026
Step 87: 68026 + 791 = 68817
Step 88: 68817 + 791 = 69608
Step 89: 69608 + 791 = 70399
Step 90: 70399 + 791 = 71190
Step 91: 71190 + 791 = 71981
Step 92: 71981 + 791 = 72772
Step 93: 72772 + 791 = 73563
Step 94: 73563 + 791 = 74354
Step 95: 74354 + 791 = 75145
Step 96: 75145 + 791 = 75936
Step 97: 75936 + 791 = 76727
Step 98: 76727 + 791 = 77518
Step 99: 77518 + 791 = 78309
Step 100: 78309 + 791 = 79100
Step 101: 79100 + 791 = 79891
Step 102: 79891 + 791 = 80682
Step 103: 80682 + 791 = 81473
Step 104: 81473 + 791 = 82264
Step 105: 82264 + 791 = 83055
Step 106: 83055 + 791 = 83846
Step 107: 83846 + 791 = 84637
Step 108: 84637 + 791 = 85428
Step 109: 85428 + 791 = 86219
Step 110: 86219 + 791 = 87010
Step 111: 87010 + 791 = 87801
Step 112: 87801 + 791 = 88592
Step 113: 88592 + 791 = 89383
Step 114: 89383 + 791 = 90174
Step 115: 90174 + 791 = 90965
Step 116: 90965 + 791 = 91756
Step 117: 91756 + 791 = 92547
Step 118: 92547 + 791 = 93338
Step 119: 93338 + 791 = 94129
Step 120: 94129 + 791 = 94920
Step 121: 94920 + 791 = 95711
Step 122: 95711 + 791 = 96502
Step 123: 96502 + 791 = 97293
Step 124: 97293 + 791 = 98084
Step 125: 98084 + 791 = 98875
Step 126: 98875 + 791 = 99666
Step 127: 99666 + 791 = 100457
Step 128: 100457 + 791 = 101248
Step 129: 101248 + 791 = 102039
Step 130: 102039 + 791 = 102830
Step 131: 102830 + 791 = 103621
Step 132: 103621 + 791 = 104412
Step 133: 104412 + 791 = 105203
Step 134: 105203 + 791 = 105994
Step 135: 105994 + 791 = 106785
Step 136: 106785 + 791 = 107576
Step 137: 107576 + 791 = 108367
Step 138: 108367 + 791 = 109158
Step 139: 109158 + 791 = 109949
Step 140: 109949 + 791 = 110740
Step 141: 110740 + 791 = 111531
Step 142: 111531 + 791 = 112322
Step 143: 112322 + 791 = 113113
Step 144: 113113 + 791 = 113904
Step 145: 113904 + 791 = 114695
Step 146: 114695 + 791 = 115486
Step 147: 115486 + 791 = 116277
Step 148: 116277 + 791 = 117068
Step 149: 117068 + 791 = 117859
Step 150: 117859 + 791 = 118650
Step 151: 118650 + 791 = 119441
Step 152: 119441 + 791 = 120232
Step 153: 120232 + 791 = 121023

So, 791*153 = 121023