OK, let's work through this together. We're starting with 257 and we're going to multiply it by 102, which means we add 257 to itself 102 times.
Step 1: 0 + 257 = 257
Step 2: 257 + 257 = 514
Step 3: 514 + 257 = 771
Step 4: 771 + 257 = 1028
Step 5: 1028 + 257 = 1285
Step 6: 1285 + 257 = 1542
Step 7: 1542 + 257 = 1799
Step 8: 1799 + 257 = 2056
Step 9: 2056 + 257 = 2313
Step 10: 2313 + 257 = 2570
Step 11: 2570 + 257 = 2827
Step 12: 2827 + 257 = 3084
Step 13: 3084 + 257 = 3341
Step 14: 3341 + 257 = 3598
Step 15: 3598 + 257 = 3855
Step 16: 3855 + 257 = 4112
Step 17: 4112 + 257 = 4369
Step 18: 4369 + 257 = 4626
Step 19: 4626 + 257 = 4883
Step 20: 4883 + 257 = 5140
Step 21: 5140 + 257 = 5397
Step 22: 5397 + 257 = 5654
Step 23: 5654 + 257 = 5911
Step 24: 5911 + 257 = 6168
Step 25: 6168 + 257 = 6425
Step 26: 6425 + 257 = 6682
Step 27: 6682 + 257 = 6939
Step 28: 6939 + 257 = 7196
Step 29: 7196 + 257 = 7453
Step 30: 7453 + 257 = 7710
Step 31: 7710 + 257 = 7967
Step 32: 7967 + 257 = 8224
Step 33: 8224 + 257 = 8481
Step 34: 8481 + 257 = 8738
Step 35: 8738 + 257 = 8995
Step 36: 8995 + 257 = 9252
Step 37: 9252 + 257 = 9509
Step 38: 9509 + 257 = 9766
Step 39: 9766 + 257 = 10023
Step 40: 10023 + 257 = 10280
Step 41: 10280 + 257 = 10537
Step 42: 10537 + 257 = 10794
Step 43: 10794 + 257 = 11051
Step 44: 11051 + 257 = 11308
Step 45: 11308 + 257 = 11565
Step 46: 11565 + 257 = 11822
Step 47: 11822 + 257 = 12079
Step 48: 12079 + 257 = 12336
Step 49: 12336 + 257 = 12593
Step 50: 12593 + 257 = 12850
Step 51: 12850 + 257 = 13107
Step 52: 13107 + 257 = 13364
Step 53: 13364 + 257 = 13621
Step 54: 13621 + 257 = 13878
Step 55: 13878 + 257 = 14135
Step 56: 14135 + 257 = 14392
Step 57: 14392 + 257 = 14649
Step 58: 14649 + 257 = 14906
Step 59: 14906 + 257 = 15163
Step 60: 15163 + 257 = 15420
Step 61: 15420 + 257 = 15677
Step 62: 15677 + 257 = 15934
Step 63: 15934 + 257 = 16191
Step 64: 16191 + 257 = 16448
Step 65: 16448 + 257 = 16705
Step 66: 16705 + 257 = 16962
Step 67: 16962 + 257 = 17219
Step 68: 17219 + 257 = 17476
Step 69: 17476 + 257 = 17733
Step 70: 17733 + 257 = 17990
Step 71: 17990 + 257 = 18247
Step 72: 18247 + 257 = 18504
Step 73: 18504 + 257 = 18761
Step 74: 18761 + 257 = 19018
Step 75: 19018 + 257 = 19275
Step 76: 19275 + 257 = 19532
Step 77: 19532 + 257 = 19789
Step 78: 19789 + 257 = 20046
Step 79: 20046 + 257 = 20303
Step 80: 20303 + 257 = 20560
Step 81: 20560 + 257 = 20817
Step 82: 20817 + 257 = 21074
Step 83: 21074 + 257 = 21331
Step 84: 21331 + 257 = 21588
Step 85: 21588 + 257 = 21845
Step 86: 21845 + 257 = 22102
Step 87: 22102 + 257 = 22359
Step 88: 22359 + 257 = 22616
Step 89: 22616 + 257 = 22873
Step 90: 22873 + 257 = 23130
Step 91: 23130 + 257 = 23387
Step 92: 23387 + 257 = 23644
Step 93: 23644 + 257 = 23901
Step 94: 23901 + 257 = 24158
Step 95: 24158 + 257 = 24415
Step 96: 24415 + 257 = 24672
Step 97: 24672 + 257 = 24929
Step 98: 24929 + 257 = 25186
Step 99: 25186 + 257 = 25443
Step 100: 25443 + 257 = 25700
Step 101: 25700 + 257 = 25957
Step 102: 25957 + 257 = 26214

So, 257*102 = 26214