OK, let's work through this together. We're starting with 667 and we're going to multiply it by 210, which means we add 667 to itself 210 times.
Step 1: 0 + 667 = 667
Step 2: 667 + 667 = 1334
Step 3: 1334 + 667 = 2001
Step 4: 2001 + 667 = 2668
Step 5: 2668 + 667 = 3335
Step 6: 3335 + 667 = 4002
Step 7: 4002 + 667 = 4669
Step 8: 4669 + 667 = 5336
Step 9: 5336 + 667 = 6003
Step 10: 6003 + 667 = 6670
Step 11: 6670 + 667 = 7337
Step 12: 7337 + 667 = 8004
Step 13: 8004 + 667 = 8671
Step 14: 8671 + 667 = 9338
Step 15: 9338 + 667 = 10005
Step 16: 10005 + 667 = 10672
Step 17: 10672 + 667 = 11339
Step 18: 11339 + 667 = 12006
Step 19: 12006 + 667 = 12673
Step 20: 12673 + 667 = 13340
Step 21: 13340 + 667 = 14007
Step 22: 14007 + 667 = 14674
Step 23: 14674 + 667 = 15341
Step 24: 15341 + 667 = 16008
Step 25: 16008 + 667 = 16675
Step 26: 16675 + 667 = 17342
Step 27: 17342 + 667 = 18009
Step 28: 18009 + 667 = 18676
Step 29: 18676 + 667 = 19343
Step 30: 19343 + 667 = 20010
Step 31: 20010 + 667 = 20677
Step 32: 20677 + 667 = 21344
Step 33: 21344 + 667 = 22011
Step 34: 22011 + 667 = 22678
Step 35: 22678 + 667 = 23345
Step 36: 23345 + 667 = 24012
Step 37: 24012 + 667 = 24679
Step 38: 24679 + 667 = 25346
Step 39: 25346 + 667 = 26013
Step 40: 26013 + 667 = 26680
Step 41: 26680 + 667 = 27347
Step 42: 27347 + 667 = 28014
Step 43: 28014 + 667 = 28681
Step 44: 28681 + 667 = 29348
Step 45: 29348 + 667 = 30015
Step 46: 30015 + 667 = 30682
Step 47: 30682 + 667 = 31349
Step 48: 31349 + 667 = 32016
Step 49: 32016 + 667 = 32683
Step 50: 32683 + 667 = 33350
Step 51: 33350 + 667 = 34017
Step 52: 34017 + 667 = 34684
Step 53: 34684 + 667 = 35351
Step 54: 35351 + 667 = 36018
Step 55: 36018 + 667 = 36685
Step 56: 36685 + 667 = 37352
Step 57: 37352 + 667 = 38019
Step 58: 38019 + 667 = 38686
Step 59: 38686 + 667 = 39353
Step 60: 39353 + 667 = 40020
Step 61: 40020 + 667 = 40687
Step 62: 40687 + 667 = 41354
Step 63: 41354 + 667 = 42021
Step 64: 42021 + 667 = 42688
Step 65: 42688 + 667 = 43355
Step 66: 43355 + 667 = 44022
Step 67: 44022 + 667 = 44689
Step 68: 44689 + 667 = 45356
Step 69: 45356 + 667 = 46023
Step 70: 46023 + 667 = 46690
Step 71: 46690 + 667 = 47357
Step 72: 47357 + 667 = 48024
Step 73: 48024 + 667 = 48691
Step 74: 48691 + 667 = 49358
Step 75: 49358 + 667 = 50025
Step 76: 50025 + 667 = 50692
Step 77: 50692 + 667 = 51359
Step 78: 51359 + 667 = 52026
Step 79: 52026 + 667 = 52693
Step 80: 52693 + 667 = 53360
Step 81: 53360 + 667 = 54027
Step 82: 54027 + 667 = 54694
Step 83: 54694 + 667 = 55361
Step 84: 55361 + 667 = 56028
Step 85: 56028 + 667 = 56695
Step 86: 56695 + 667 = 57362
Step 87: 57362 + 667 = 58029
Step 88: 58029 + 667 = 58696
Step 89: 58696 + 667 = 59363
Step 90: 59363 + 667 = 60030
Step 91: 60030 + 667 = 60697
Step 92: 60697 + 667 = 61364
Step 93: 61364 + 667 = 62031
Step 94: 62031 + 667 = 62698
Step 95: 62698 + 667 = 63365
Step 96: 63365 + 667 = 64032
Step 97: 64032 + 667 = 64699
Step 98: 64699 + 667 = 65366
Step 99: 65366 + 667 = 66033
Step 100: 66033 + 667 = 66700
Step 101: 66700 + 667 = 67367
Step 102: 67367 + 667 = 68034
Step 103: 68034 + 667 = 68701
Step 104: 68701 + 667 = 69368
Step 105: 69368 + 667 = 70035
Step 106: 70035 + 667 = 70702
Step 107: 70702 + 667 = 71369
Step 108: 71369 + 667 = 72036
Step 109: 72036 + 667 = 72703
Step 110: 72703 + 667 = 73370
Step 111: 73370 + 667 = 74037
Step 112: 74037 + 667 = 74704
Step 113: 74704 + 667 = 75371
Step 114: 75371 + 667 = 76038
Step 115: 76038 + 667 = 76705
Step 116: 76705 + 667 = 77372
Step 117: 77372 + 667 = 78039
Step 118: 78039 + 667 = 78706
Step 119: 78706 + 667 = 79373
Step 120: 79373 + 667 = 80040
Step 121: 80040 + 667 = 80707
Step 122: 80707 + 667 = 81374
Step 123: 81374 + 667 = 82041
Step 124: 82041 + 667 = 82708
Step 125: 82708 + 667 = 83375
Step 126: 83375 + 667 = 84042
Step 127: 84042 + 667 = 84709
Step 128: 84709 + 667 = 85376
Step 129: 85376 + 667 = 86043
Step 130: 86043 + 667 = 86710
Step 131: 86710 + 667 = 87377
Step 132: 87377 + 667 = 88044
Step 133: 88044 + 667 = 88711
Step 134: 88711 + 667 = 89378
Step 135: 89378 + 667 = 90045
Step 136: 90045 + 667 = 90712
Step 137: 90712 + 667 = 91379
Step 138: 91379 + 667 = 92046
Step 139: 92046 + 667 = 92713
Step 140: 92713 + 667 = 93380
Step 141: 93380 + 667 = 94047
Step 142: 94047 + 667 = 94714
Step 143: 94714 + 667 = 95381
Step 144: 95381 + 667 = 96048
Step 145: 96048 + 667 = 96715
Step 146: 96715 + 667 = 97382
Step 147: 97382 + 667 = 98049
Step 148: 98049 + 667 = 98716
Step 149: 98716 + 667 = 99383
Step 150: 99383 + 667 = 100050
Step 151: 100050 + 667 = 100717
Step 152: 100717 + 667 = 101384
Step 153: 101384 + 667 = 102051
Step 154: 102051 + 667 = 102718
Step 155: 102718 + 667 = 103385
Step 156: 103385 + 667 = 104052
Step 157: 104052 + 667 = 104719
Step 158: 104719 + 667 = 105386
Step 159: 105386 + 667 = 106053
Step 160: 106053 + 667 = 106720
Step 161: 106720 + 667 = 107387
Step 162: 107387 + 667 = 108054
Step 163: 108054 + 667 = 108721
Step 164: 108721 + 667 = 109388
Step 165: 109388 + 667 = 110055
Step 166: 110055 + 667 = 110722
Step 167: 110722 + 667 = 111389
Step 168: 111389 + 667 = 112056
Step 169: 112056 + 667 = 112723
Step 170: 112723 + 667 = 113390
Step 171: 113390 + 667 = 114057
Step 172: 114057 + 667 = 114724
Step 173: 114724 + 667 = 115391
Step 174: 115391 + 667 = 116058
Step 175: 116058 + 667 = 116725
Step 176: 116725 + 667 = 117392
Step 177: 117392 + 667 = 118059
Step 178: 118059 + 667 = 118726
Step 179: 118726 + 667 = 119393
Step 180: 119393 + 667 = 120060
Step 181: 120060 + 667 = 120727
Step 182: 120727 + 667 = 121394
Step 183: 121394 + 667 = 122061
Step 184: 122061 + 667 = 122728
Step 185: 122728 + 667 = 123395
Step 186: 123395 + 667 = 124062
Step 187: 124062 + 667 = 124729
Step 188: 124729 + 667 = 125396
Step 189: 125396 + 667 = 126063
Step 190: 126063 + 667 = 126730
Step 191: 126730 + 667 = 127397
Step 192: 127397 + 667 = 128064
Step 193: 128064 + 667 = 128731
Step 194: 128731 + 667 = 129398
Step 195: 129398 + 667 = 130065
Step 196: 130065 + 667 = 130732
Step 197: 130732 + 667 = 131399
Step 198: 131399 + 667 = 132066
Step 199: 132066 + 667 = 132733
Step 200: 132733 + 667 = 133400
Step 201: 133400 + 667 = 134067
Step 202: 134067 + 667 = 134734
Step 203: 134734 + 667 = 135401
Step 204: 135401 + 667 = 136068
Step 205: 136068 + 667 = 136735
Step 206: 136735 + 667 = 137402
Step 207: 137402 + 667 = 138069
Step 208: 138069 + 667 = 138736
Step 209: 138736 + 667 = 139403
Step 210: 139403 + 667 = 140070

So, 667*210 = 140070