OK, let's crack this. We're given 388 and our task is to multiply it by 100. Essentially, we'll be adding 388 to itself 100 times.
Step 1: 0 + 388 = 388
Step 2: 388 + 388 = 776
Step 3: 776 + 388 = 1164
Step 4: 1164 + 388 = 1552
Step 5: 1552 + 388 = 1940
Step 6: 1940 + 388 = 2328
Step 7: 2328 + 388 = 2716
Step 8: 2716 + 388 = 3104
Step 9: 3104 + 388 = 3492
Step 10: 3492 + 388 = 3880
Step 11: 3880 + 388 = 4268
Step 12: 4268 + 388 = 4656
Step 13: 4656 + 388 = 5044
Step 14: 5044 + 388 = 5432
Step 15: 5432 + 388 = 5820
Step 16: 5820 + 388 = 6208
Step 17: 6208 + 388 = 6596
Step 18: 6596 + 388 = 6984
Step 19: 6984 + 388 = 7372
Step 20: 7372 + 388 = 7760
Step 21: 7760 + 388 = 8148
Step 22: 8148 + 388 = 8536
Step 23: 8536 + 388 = 8924
Step 24: 8924 + 388 = 9312
Step 25: 9312 + 388 = 9700
Step 26: 9700 + 388 = 10088
Step 27: 10088 + 388 = 10476
Step 28: 10476 + 388 = 10864
Step 29: 10864 + 388 = 11252
Step 30: 11252 + 388 = 11640
Step 31: 11640 + 388 = 12028
Step 32: 12028 + 388 = 12416
Step 33: 12416 + 388 = 12804
Step 34: 12804 + 388 = 13192
Step 35: 13192 + 388 = 13580
Step 36: 13580 + 388 = 13968
Step 37: 13968 + 388 = 14356
Step 38: 14356 + 388 = 14744
Step 39: 14744 + 388 = 15132
Step 40: 15132 + 388 = 15520
Step 41: 15520 + 388 = 15908
Step 42: 15908 + 388 = 16296
Step 43: 16296 + 388 = 16684
Step 44: 16684 + 388 = 17072
Step 45: 17072 + 388 = 17460
Step 46: 17460 + 388 = 17848
Step 47: 17848 + 388 = 18236
Step 48: 18236 + 388 = 18624
Step 49: 18624 + 388 = 19012
Step 50: 19012 + 388 = 19400
Step 51: 19400 + 388 = 19788
Step 52: 19788 + 388 = 20176
Step 53: 20176 + 388 = 20564
Step 54: 20564 + 388 = 20952
Step 55: 20952 + 388 = 21340
Step 56: 21340 + 388 = 21728
Step 57: 21728 + 388 = 22116
Step 58: 22116 + 388 = 22504
Step 59: 22504 + 388 = 22892
Step 60: 22892 + 388 = 23280
Step 61: 23280 + 388 = 23668
Step 62: 23668 + 388 = 24056
Step 63: 24056 + 388 = 24444
Step 64: 24444 + 388 = 24832
Step 65: 24832 + 388 = 25220
Step 66: 25220 + 388 = 25608
Step 67: 25608 + 388 = 25996
Step 68: 25996 + 388 = 26384
Step 69: 26384 + 388 = 26772
Step 70: 26772 + 388 = 27160
Step 71: 27160 + 388 = 27548
Step 72: 27548 + 388 = 27936
Step 73: 27936 + 388 = 28324
Step 74: 28324 + 388 = 28712
Step 75: 28712 + 388 = 29100
Step 76: 29100 + 388 = 29488
Step 77: 29488 + 388 = 29876
Step 78: 29876 + 388 = 30264
Step 79: 30264 + 388 = 30652
Step 80: 30652 + 388 = 31040
Step 81: 31040 + 388 = 31428
Step 82: 31428 + 388 = 31816
Step 83: 31816 + 388 = 32204
Step 84: 32204 + 388 = 32592
Step 85: 32592 + 388 = 32980
Step 86: 32980 + 388 = 33368
Step 87: 33368 + 388 = 33756
Step 88: 33756 + 388 = 34144
Step 89: 34144 + 388 = 34532
Step 90: 34532 + 388 = 34920
Step 91: 34920 + 388 = 35308
Step 92: 35308 + 388 = 35696
Step 93: 35696 + 388 = 36084
Step 94: 36084 + 388 = 36472
Step 95: 36472 + 388 = 36860
Step 96: 36860 + 388 = 37248
Step 97: 37248 + 388 = 37636
Step 98: 37636 + 388 = 38024
Step 99: 38024 + 388 = 38412
Step 100: 38412 + 388 = 38800

So, 388*100 = 38800