OK, let's work through this together. We're starting with 637 and we're going to multiply it by 418, which means we add 637 to itself 418 times.
Step 1: 0 + 637 = 637
Step 2: 637 + 637 = 1274
Step 3: 1274 + 637 = 1911
Step 4: 1911 + 637 = 2548
Step 5: 2548 + 637 = 3185
Step 6: 3185 + 637 = 3822
Step 7: 3822 + 637 = 4459
Step 8: 4459 + 637 = 5096
Step 9: 5096 + 637 = 5733
Step 10: 5733 + 637 = 6370
Step 11: 6370 + 637 = 7007
Step 12: 7007 + 637 = 7644
Step 13: 7644 + 637 = 8281
Step 14: 8281 + 637 = 8918
Step 15: 8918 + 637 = 9555
Step 16: 9555 + 637 = 10192
Step 17: 10192 + 637 = 10829
Step 18: 10829 + 637 = 11466
Step 19: 11466 + 637 = 12103
Step 20: 12103 + 637 = 12740
Step 21: 12740 + 637 = 13377
Step 22: 13377 + 637 = 14014
Step 23: 14014 + 637 = 14651
Step 24: 14651 + 637 = 15288
Step 25: 15288 + 637 = 15925
Step 26: 15925 + 637 = 16562
Step 27: 16562 + 637 = 17199
Step 28: 17199 + 637 = 17836
Step 29: 17836 + 637 = 18473
Step 30: 18473 + 637 = 19110
Step 31: 19110 + 637 = 19747
Step 32: 19747 + 637 = 20384
Step 33: 20384 + 637 = 21021
Step 34: 21021 + 637 = 21658
Step 35: 21658 + 637 = 22295
Step 36: 22295 + 637 = 22932
Step 37: 22932 + 637 = 23569
Step 38: 23569 + 637 = 24206
Step 39: 24206 + 637 = 24843
Step 40: 24843 + 637 = 25480
Step 41: 25480 + 637 = 26117
Step 42: 26117 + 637 = 26754
Step 43: 26754 + 637 = 27391
Step 44: 27391 + 637 = 28028
Step 45: 28028 + 637 = 28665
Step 46: 28665 + 637 = 29302
Step 47: 29302 + 637 = 29939
Step 48: 29939 + 637 = 30576
Step 49: 30576 + 637 = 31213
Step 50: 31213 + 637 = 31850
Step 51: 31850 + 637 = 32487
Step 52: 32487 + 637 = 33124
Step 53: 33124 + 637 = 33761
Step 54: 33761 + 637 = 34398
Step 55: 34398 + 637 = 35035
Step 56: 35035 + 637 = 35672
Step 57: 35672 + 637 = 36309
Step 58: 36309 + 637 = 36946
Step 59: 36946 + 637 = 37583
Step 60: 37583 + 637 = 38220
Step 61: 38220 + 637 = 38857
Step 62: 38857 + 637 = 39494
Step 63: 39494 + 637 = 40131
Step 64: 40131 + 637 = 40768
Step 65: 40768 + 637 = 41405
Step 66: 41405 + 637 = 42042
Step 67: 42042 + 637 = 42679
Step 68: 42679 + 637 = 43316
Step 69: 43316 + 637 = 43953
Step 70: 43953 + 637 = 44590
Step 71: 44590 + 637 = 45227
Step 72: 45227 + 637 = 45864
Step 73: 45864 + 637 = 46501
Step 74: 46501 + 637 = 47138
Step 75: 47138 + 637 = 47775
Step 76: 47775 + 637 = 48412
Step 77: 48412 + 637 = 49049
Step 78: 49049 + 637 = 49686
Step 79: 49686 + 637 = 50323
Step 80: 50323 + 637 = 50960
Step 81: 50960 + 637 = 51597
Step 82: 51597 + 637 = 52234
Step 83: 52234 + 637 = 52871
Step 84: 52871 + 637 = 53508
Step 85: 53508 + 637 = 54145
Step 86: 54145 + 637 = 54782
Step 87: 54782 + 637 = 55419
Step 88: 55419 + 637 = 56056
Step 89: 56056 + 637 = 56693
Step 90: 56693 + 637 = 57330
Step 91: 57330 + 637 = 57967
Step 92: 57967 + 637 = 58604
Step 93: 58604 + 637 = 59241
Step 94: 59241 + 637 = 59878
Step 95: 59878 + 637 = 60515
Step 96: 60515 + 637 = 61152
Step 97: 61152 + 637 = 61789
Step 98: 61789 + 637 = 62426
Step 99: 62426 + 637 = 63063
Step 100: 63063 + 637 = 63700
Step 101: 63700 + 637 = 64337
Step 102: 64337 + 637 = 64974
Step 103: 64974 + 637 = 65611
Step 104: 65611 + 637 = 66248
Step 105: 66248 + 637 = 66885
Step 106: 66885 + 637 = 67522
Step 107: 67522 + 637 = 68159
Step 108: 68159 + 637 = 68796
Step 109: 68796 + 637 = 69433
Step 110: 69433 + 637 = 70070
Step 111: 70070 + 637 = 70707
Step 112: 70707 + 637 = 71344
Step 113: 71344 + 637 = 71981
Step 114: 71981 + 637 = 72618
Step 115: 72618 + 637 = 73255
Step 116: 73255 + 637 = 73892
Step 117: 73892 + 637 = 74529
Step 118: 74529 + 637 = 75166
Step 119: 75166 + 637 = 75803
Step 120: 75803 + 637 = 76440
Step 121: 76440 + 637 = 77077
Step 122: 77077 + 637 = 77714
Step 123: 77714 + 637 = 78351
Step 124: 78351 + 637 = 78988
Step 125: 78988 + 637 = 79625
Step 126: 79625 + 637 = 80262
Step 127: 80262 + 637 = 80899
Step 128: 80899 + 637 = 81536
Step 129: 81536 + 637 = 82173
Step 130: 82173 + 637 = 82810
Step 131: 82810 + 637 = 83447
Step 132: 83447 + 637 = 84084
Step 133: 84084 + 637 = 84721
Step 134: 84721 + 637 = 85358
Step 135: 85358 + 637 = 85995
Step 136: 85995 + 637 = 86632
Step 137: 86632 + 637 = 87269
Step 138: 87269 + 637 = 87906
Step 139: 87906 + 637 = 88543
Step 140: 88543 + 637 = 89180
Step 141: 89180 + 637 = 89817
Step 142: 89817 + 637 = 90454
Step 143: 90454 + 637 = 91091
Step 144: 91091 + 637 = 91728
Step 145: 91728 + 637 = 92365
Step 146: 92365 + 637 = 93002
Step 147: 93002 + 637 = 93639
Step 148: 93639 + 637 = 94276
Step 149: 94276 + 637 = 94913
Step 150: 94913 + 637 = 95550
Step 151: 95550 + 637 = 96187
Step 152: 96187 + 637 = 96824
Step 153: 96824 + 637 = 97461
Step 154: 97461 + 637 = 98098
Step 155: 98098 + 637 = 98735
Step 156: 98735 + 637 = 99372
Step 157: 99372 + 637 = 100009
Step 158: 100009 + 637 = 100646
Step 159: 100646 + 637 = 101283
Step 160: 101283 + 637 = 101920
Step 161: 101920 + 637 = 102557
Step 162: 102557 + 637 = 103194
Step 163: 103194 + 637 = 103831
Step 164: 103831 + 637 = 104468
Step 165: 104468 + 637 = 105105
Step 166: 105105 + 637 = 105742
Step 167: 105742 + 637 = 106379
Step 168: 106379 + 637 = 107016
Step 169: 107016 + 637 = 107653
Step 170: 107653 + 637 = 108290
Step 171: 108290 + 637 = 108927
Step 172: 108927 + 637 = 109564
Step 173: 109564 + 637 = 110201
Step 174: 110201 + 637 = 110838
Step 175: 110838 + 637 = 111475
Step 176: 111475 + 637 = 112112
Step 177: 112112 + 637 = 112749
Step 178: 112749 + 637 = 113386
Step 179: 113386 + 637 = 114023
Step 180: 114023 + 637 = 114660
Step 181: 114660 + 637 = 115297
Step 182: 115297 + 637 = 115934
Step 183: 115934 + 637 = 116571
Step 184: 116571 + 637 = 117208
Step 185: 117208 + 637 = 117845
Step 186: 117845 + 637 = 118482
Step 187: 118482 + 637 = 119119
Step 188: 119119 + 637 = 119756
Step 189: 119756 + 637 = 120393
Step 190: 120393 + 637 = 121030
Step 191: 121030 + 637 = 121667
Step 192: 121667 + 637 = 122304
Step 193: 122304 + 637 = 122941
Step 194: 122941 + 637 = 123578
Step 195: 123578 + 637 = 124215
Step 196: 124215 + 637 = 124852
Step 197: 124852 + 637 = 125489
Step 198: 125489 + 637 = 126126
Step 199: 126126 + 637 = 126763
Step 200: 126763 + 637 = 127400
Step 201: 127400 + 637 = 128037
Step 202: 128037 + 637 = 128674
Step 203: 128674 + 637 = 129311
Step 204: 129311 + 637 = 129948
Step 205: 129948 + 637 = 130585
Step 206: 130585 + 637 = 131222
Step 207: 131222 + 637 = 131859
Step 208: 131859 + 637 = 132496
Step 209: 132496 + 637 = 133133
Step 210: 133133 + 637 = 133770
Step 211: 133770 + 637 = 134407
Step 212: 134407 + 637 = 135044
Step 213: 135044 + 637 = 135681
Step 214: 135681 + 637 = 136318
Step 215: 136318 + 637 = 136955
Step 216: 136955 + 637 = 137592
Step 217: 137592 + 637 = 138229
Step 218: 138229 + 637 = 138866
Step 219: 138866 + 637 = 139503
Step 220: 139503 + 637 = 140140
Step 221: 140140 + 637 = 140777
Step 222: 140777 + 637 = 141414
Step 223: 141414 + 637 = 142051
Step 224: 142051 + 637 = 142688
Step 225: 142688 + 637 = 143325
Step 226: 143325 + 637 = 143962
Step 227: 143962 + 637 = 144599
Step 228: 144599 + 637 = 145236
Step 229: 145236 + 637 = 145873
Step 230: 145873 + 637 = 146510
Step 231: 146510 + 637 = 147147
Step 232: 147147 + 637 = 147784
Step 233: 147784 + 637 = 148421
Step 234: 148421 + 637 = 149058
Step 235: 149058 + 637 = 149695
Step 236: 149695 + 637 = 150332
Step 237: 150332 + 637 = 150969
Step 238: 150969 + 637 = 151606
Step 239: 151606 + 637 = 152243
Step 240: 152243 + 637 = 152880
Step 241: 152880 + 637 = 153517
Step 242: 153517 + 637 = 154154
Step 243: 154154 + 637 = 154791
Step 244: 154791 + 637 = 155428
Step 245: 155428 + 637 = 156065
Step 246: 156065 + 637 = 156702
Step 247: 156702 + 637 = 157339
Step 248: 157339 + 637 = 157976
Step 249: 157976 + 637 = 158613
Step 250: 158613 + 637 = 159250
Step 251: 159250 + 637 = 159887
Step 252: 159887 + 637 = 160524
Step 253: 160524 + 637 = 161161
Step 254: 161161 + 637 = 161798
Step 255: 161798 + 637 = 162435
Step 256: 162435 + 637 = 163072
Step 257: 163072 + 637 = 163709
Step 258: 163709 + 637 = 164346
Step 259: 164346 + 637 = 164983
Step 260: 164983 + 637 = 165620
Step 261: 165620 + 637 = 166257
Step 262: 166257 + 637 = 166894
Step 263: 166894 + 637 = 167531
Step 264: 167531 + 637 = 168168
Step 265: 168168 + 637 = 168805
Step 266: 168805 + 637 = 169442
Step 267: 169442 + 637 = 170079
Step 268: 170079 + 637 = 170716
Step 269: 170716 + 637 = 171353
Step 270: 171353 + 637 = 171990
Step 271: 171990 + 637 = 172627
Step 272: 172627 + 637 = 173264
Step 273: 173264 + 637 = 173901
Step 274: 173901 + 637 = 174538
Step 275: 174538 + 637 = 175175
Step 276: 175175 + 637 = 175812
Step 277: 175812 + 637 = 176449
Step 278: 176449 + 637 = 177086
Step 279: 177086 + 637 = 177723
Step 280: 177723 + 637 = 178360
Step 281: 178360 + 637 = 178997
Step 282: 178997 + 637 = 179634
Step 283: 179634 + 637 = 180271
Step 284: 180271 + 637 = 180908
Step 285: 180908 + 637 = 181545
Step 286: 181545 + 637 = 182182
Step 287: 182182 + 637 = 182819
Step 288: 182819 + 637 = 183456
Step 289: 183456 + 637 = 184093
Step 290: 184093 + 637 = 184730
Step 291: 184730 + 637 = 185367
Step 292: 185367 + 637 = 186004
Step 293: 186004 + 637 = 186641
Step 294: 186641 + 637 = 187278
Step 295: 187278 + 637 = 187915
Step 296: 187915 + 637 = 188552
Step 297: 188552 + 637 = 189189
Step 298: 189189 + 637 = 189826
Step 299: 189826 + 637 = 190463
Step 300: 190463 + 637 = 191100
Step 301: 191100 + 637 = 191737
Step 302: 191737 + 637 = 192374
Step 303: 192374 + 637 = 193011
Step 304: 193011 + 637 = 193648
Step 305: 193648 + 637 = 194285
Step 306: 194285 + 637 = 194922
Step 307: 194922 + 637 = 195559
Step 308: 195559 + 637 = 196196
Step 309: 196196 + 637 = 196833
Step 310: 196833 + 637 = 197470
Step 311: 197470 + 637 = 198107
Step 312: 198107 + 637 = 198744
Step 313: 198744 + 637 = 199381
Step 314: 199381 + 637 = 200018
Step 315: 200018 + 637 = 200655
Step 316: 200655 + 637 = 201292
Step 317: 201292 + 637 = 201929
Step 318: 201929 + 637 = 202566
Step 319: 202566 + 637 = 203203
Step 320: 203203 + 637 = 203840
Step 321: 203840 + 637 = 204477
Step 322: 204477 + 637 = 205114
Step 323: 205114 + 637 = 205751
Step 324: 205751 + 637 = 206388
Step 325: 206388 + 637 = 207025
Step 326: 207025 + 637 = 207662
Step 327: 207662 + 637 = 208299
Step 328: 208299 + 637 = 208936
Step 329: 208936 + 637 = 209573
Step 330: 209573 + 637 = 210210
Step 331: 210210 + 637 = 210847
Step 332: 210847 + 637 = 211484
Step 333: 211484 + 637 = 212121
Step 334: 212121 + 637 = 212758
Step 335: 212758 + 637 = 213395
Step 336: 213395 + 637 = 214032
Step 337: 214032 + 637 = 214669
Step 338: 214669 + 637 = 215306
Step 339: 215306 + 637 = 215943
Step 340: 215943 + 637 = 216580
Step 341: 216580 + 637 = 217217
Step 342: 217217 + 637 = 217854
Step 343: 217854 + 637 = 218491
Step 344: 218491 + 637 = 219128
Step 345: 219128 + 637 = 219765
Step 346: 219765 + 637 = 220402
Step 347: 220402 + 637 = 221039
Step 348: 221039 + 637 = 221676
Step 349: 221676 + 637 = 222313
Step 350: 222313 + 637 = 222950
Step 351: 222950 + 637 = 223587
Step 352: 223587 + 637 = 224224
Step 353: 224224 + 637 = 224861
Step 354: 224861 + 637 = 225498
Step 355: 225498 + 637 = 226135
Step 356: 226135 + 637 = 226772
Step 357: 226772 + 637 = 227409
Step 358: 227409 + 637 = 228046
Step 359: 228046 + 637 = 228683
Step 360: 228683 + 637 = 229320
Step 361: 229320 + 637 = 229957
Step 362: 229957 + 637 = 230594
Step 363: 230594 + 637 = 231231
Step 364: 231231 + 637 = 231868
Step 365: 231868 + 637 = 232505
Step 366: 232505 + 637 = 233142
Step 367: 233142 + 637 = 233779
Step 368: 233779 + 637 = 234416
Step 369: 234416 + 637 = 235053
Step 370: 235053 + 637 = 235690
Step 371: 235690 + 637 = 236327
Step 372: 236327 + 637 = 236964
Step 373: 236964 + 637 = 237601
Step 374: 237601 + 637 = 238238
Step 375: 238238 + 637 = 238875
Step 376: 238875 + 637 = 239512
Step 377: 239512 + 637 = 240149
Step 378: 240149 + 637 = 240786
Step 379: 240786 + 637 = 241423
Step 380: 241423 + 637 = 242060
Step 381: 242060 + 637 = 242697
Step 382: 242697 + 637 = 243334
Step 383: 243334 + 637 = 243971
Step 384: 243971 + 637 = 244608
Step 385: 244608 + 637 = 245245
Step 386: 245245 + 637 = 245882
Step 387: 245882 + 637 = 246519
Step 388: 246519 + 637 = 247156
Step 389: 247156 + 637 = 247793
Step 390: 247793 + 637 = 248430
Step 391: 248430 + 637 = 249067
Step 392: 249067 + 637 = 249704
Step 393: 249704 + 637 = 250341
Step 394: 250341 + 637 = 250978
Step 395: 250978 + 637 = 251615
Step 396: 251615 + 637 = 252252
Step 397: 252252 + 637 = 252889
Step 398: 252889 + 637 = 253526
Step 399: 253526 + 637 = 254163
Step 400: 254163 + 637 = 254800
Step 401: 254800 + 637 = 255437
Step 402: 255437 + 637 = 256074
Step 403: 256074 + 637 = 256711
Step 404: 256711 + 637 = 257348
Step 405: 257348 + 637 = 257985
Step 406: 257985 + 637 = 258622
Step 407: 258622 + 637 = 259259
Step 408: 259259 + 637 = 259896
Step 409: 259896 + 637 = 260533
Step 410: 260533 + 637 = 261170
Step 411: 261170 + 637 = 261807
Step 412: 261807 + 637 = 262444
Step 413: 262444 + 637 = 263081
Step 414: 263081 + 637 = 263718
Step 415: 263718 + 637 = 264355
Step 416: 264355 + 637 = 264992
Step 417: 264992 + 637 = 265629
Step 418: 265629 + 637 = 266266

So, 637*418 = 266266