Let's roll up our sleeves and solve this. We have 851 and we're going to multiply it by 357, essentially adding 851 to itself 357 times.
Step 1: 0 + 851 = 851
Step 2: 851 + 851 = 1702
Step 3: 1702 + 851 = 2553
Step 4: 2553 + 851 = 3404
Step 5: 3404 + 851 = 4255
Step 6: 4255 + 851 = 5106
Step 7: 5106 + 851 = 5957
Step 8: 5957 + 851 = 6808
Step 9: 6808 + 851 = 7659
Step 10: 7659 + 851 = 8510
Step 11: 8510 + 851 = 9361
Step 12: 9361 + 851 = 10212
Step 13: 10212 + 851 = 11063
Step 14: 11063 + 851 = 11914
Step 15: 11914 + 851 = 12765
Step 16: 12765 + 851 = 13616
Step 17: 13616 + 851 = 14467
Step 18: 14467 + 851 = 15318
Step 19: 15318 + 851 = 16169
Step 20: 16169 + 851 = 17020
Step 21: 17020 + 851 = 17871
Step 22: 17871 + 851 = 18722
Step 23: 18722 + 851 = 19573
Step 24: 19573 + 851 = 20424
Step 25: 20424 + 851 = 21275
Step 26: 21275 + 851 = 22126
Step 27: 22126 + 851 = 22977
Step 28: 22977 + 851 = 23828
Step 29: 23828 + 851 = 24679
Step 30: 24679 + 851 = 25530
Step 31: 25530 + 851 = 26381
Step 32: 26381 + 851 = 27232
Step 33: 27232 + 851 = 28083
Step 34: 28083 + 851 = 28934
Step 35: 28934 + 851 = 29785
Step 36: 29785 + 851 = 30636
Step 37: 30636 + 851 = 31487
Step 38: 31487 + 851 = 32338
Step 39: 32338 + 851 = 33189
Step 40: 33189 + 851 = 34040
Step 41: 34040 + 851 = 34891
Step 42: 34891 + 851 = 35742
Step 43: 35742 + 851 = 36593
Step 44: 36593 + 851 = 37444
Step 45: 37444 + 851 = 38295
Step 46: 38295 + 851 = 39146
Step 47: 39146 + 851 = 39997
Step 48: 39997 + 851 = 40848
Step 49: 40848 + 851 = 41699
Step 50: 41699 + 851 = 42550
Step 51: 42550 + 851 = 43401
Step 52: 43401 + 851 = 44252
Step 53: 44252 + 851 = 45103
Step 54: 45103 + 851 = 45954
Step 55: 45954 + 851 = 46805
Step 56: 46805 + 851 = 47656
Step 57: 47656 + 851 = 48507
Step 58: 48507 + 851 = 49358
Step 59: 49358 + 851 = 50209
Step 60: 50209 + 851 = 51060
Step 61: 51060 + 851 = 51911
Step 62: 51911 + 851 = 52762
Step 63: 52762 + 851 = 53613
Step 64: 53613 + 851 = 54464
Step 65: 54464 + 851 = 55315
Step 66: 55315 + 851 = 56166
Step 67: 56166 + 851 = 57017
Step 68: 57017 + 851 = 57868
Step 69: 57868 + 851 = 58719
Step 70: 58719 + 851 = 59570
Step 71: 59570 + 851 = 60421
Step 72: 60421 + 851 = 61272
Step 73: 61272 + 851 = 62123
Step 74: 62123 + 851 = 62974
Step 75: 62974 + 851 = 63825
Step 76: 63825 + 851 = 64676
Step 77: 64676 + 851 = 65527
Step 78: 65527 + 851 = 66378
Step 79: 66378 + 851 = 67229
Step 80: 67229 + 851 = 68080
Step 81: 68080 + 851 = 68931
Step 82: 68931 + 851 = 69782
Step 83: 69782 + 851 = 70633
Step 84: 70633 + 851 = 71484
Step 85: 71484 + 851 = 72335
Step 86: 72335 + 851 = 73186
Step 87: 73186 + 851 = 74037
Step 88: 74037 + 851 = 74888
Step 89: 74888 + 851 = 75739
Step 90: 75739 + 851 = 76590
Step 91: 76590 + 851 = 77441
Step 92: 77441 + 851 = 78292
Step 93: 78292 + 851 = 79143
Step 94: 79143 + 851 = 79994
Step 95: 79994 + 851 = 80845
Step 96: 80845 + 851 = 81696
Step 97: 81696 + 851 = 82547
Step 98: 82547 + 851 = 83398
Step 99: 83398 + 851 = 84249
Step 100: 84249 + 851 = 85100
Step 101: 85100 + 851 = 85951
Step 102: 85951 + 851 = 86802
Step 103: 86802 + 851 = 87653
Step 104: 87653 + 851 = 88504
Step 105: 88504 + 851 = 89355
Step 106: 89355 + 851 = 90206
Step 107: 90206 + 851 = 91057
Step 108: 91057 + 851 = 91908
Step 109: 91908 + 851 = 92759
Step 110: 92759 + 851 = 93610
Step 111: 93610 + 851 = 94461
Step 112: 94461 + 851 = 95312
Step 113: 95312 + 851 = 96163
Step 114: 96163 + 851 = 97014
Step 115: 97014 + 851 = 97865
Step 116: 97865 + 851 = 98716
Step 117: 98716 + 851 = 99567
Step 118: 99567 + 851 = 100418
Step 119: 100418 + 851 = 101269
Step 120: 101269 + 851 = 102120
Step 121: 102120 + 851 = 102971
Step 122: 102971 + 851 = 103822
Step 123: 103822 + 851 = 104673
Step 124: 104673 + 851 = 105524
Step 125: 105524 + 851 = 106375
Step 126: 106375 + 851 = 107226
Step 127: 107226 + 851 = 108077
Step 128: 108077 + 851 = 108928
Step 129: 108928 + 851 = 109779
Step 130: 109779 + 851 = 110630
Step 131: 110630 + 851 = 111481
Step 132: 111481 + 851 = 112332
Step 133: 112332 + 851 = 113183
Step 134: 113183 + 851 = 114034
Step 135: 114034 + 851 = 114885
Step 136: 114885 + 851 = 115736
Step 137: 115736 + 851 = 116587
Step 138: 116587 + 851 = 117438
Step 139: 117438 + 851 = 118289
Step 140: 118289 + 851 = 119140
Step 141: 119140 + 851 = 119991
Step 142: 119991 + 851 = 120842
Step 143: 120842 + 851 = 121693
Step 144: 121693 + 851 = 122544
Step 145: 122544 + 851 = 123395
Step 146: 123395 + 851 = 124246
Step 147: 124246 + 851 = 125097
Step 148: 125097 + 851 = 125948
Step 149: 125948 + 851 = 126799
Step 150: 126799 + 851 = 127650
Step 151: 127650 + 851 = 128501
Step 152: 128501 + 851 = 129352
Step 153: 129352 + 851 = 130203
Step 154: 130203 + 851 = 131054
Step 155: 131054 + 851 = 131905
Step 156: 131905 + 851 = 132756
Step 157: 132756 + 851 = 133607
Step 158: 133607 + 851 = 134458
Step 159: 134458 + 851 = 135309
Step 160: 135309 + 851 = 136160
Step 161: 136160 + 851 = 137011
Step 162: 137011 + 851 = 137862
Step 163: 137862 + 851 = 138713
Step 164: 138713 + 851 = 139564
Step 165: 139564 + 851 = 140415
Step 166: 140415 + 851 = 141266
Step 167: 141266 + 851 = 142117
Step 168: 142117 + 851 = 142968
Step 169: 142968 + 851 = 143819
Step 170: 143819 + 851 = 144670
Step 171: 144670 + 851 = 145521
Step 172: 145521 + 851 = 146372
Step 173: 146372 + 851 = 147223
Step 174: 147223 + 851 = 148074
Step 175: 148074 + 851 = 148925
Step 176: 148925 + 851 = 149776
Step 177: 149776 + 851 = 150627
Step 178: 150627 + 851 = 151478
Step 179: 151478 + 851 = 152329
Step 180: 152329 + 851 = 153180
Step 181: 153180 + 851 = 154031
Step 182: 154031 + 851 = 154882
Step 183: 154882 + 851 = 155733
Step 184: 155733 + 851 = 156584
Step 185: 156584 + 851 = 157435
Step 186: 157435 + 851 = 158286
Step 187: 158286 + 851 = 159137
Step 188: 159137 + 851 = 159988
Step 189: 159988 + 851 = 160839
Step 190: 160839 + 851 = 161690
Step 191: 161690 + 851 = 162541
Step 192: 162541 + 851 = 163392
Step 193: 163392 + 851 = 164243
Step 194: 164243 + 851 = 165094
Step 195: 165094 + 851 = 165945
Step 196: 165945 + 851 = 166796
Step 197: 166796 + 851 = 167647
Step 198: 167647 + 851 = 168498
Step 199: 168498 + 851 = 169349
Step 200: 169349 + 851 = 170200
Step 201: 170200 + 851 = 171051
Step 202: 171051 + 851 = 171902
Step 203: 171902 + 851 = 172753
Step 204: 172753 + 851 = 173604
Step 205: 173604 + 851 = 174455
Step 206: 174455 + 851 = 175306
Step 207: 175306 + 851 = 176157
Step 208: 176157 + 851 = 177008
Step 209: 177008 + 851 = 177859
Step 210: 177859 + 851 = 178710
Step 211: 178710 + 851 = 179561
Step 212: 179561 + 851 = 180412
Step 213: 180412 + 851 = 181263
Step 214: 181263 + 851 = 182114
Step 215: 182114 + 851 = 182965
Step 216: 182965 + 851 = 183816
Step 217: 183816 + 851 = 184667
Step 218: 184667 + 851 = 185518
Step 219: 185518 + 851 = 186369
Step 220: 186369 + 851 = 187220
Step 221: 187220 + 851 = 188071
Step 222: 188071 + 851 = 188922
Step 223: 188922 + 851 = 189773
Step 224: 189773 + 851 = 190624
Step 225: 190624 + 851 = 191475
Step 226: 191475 + 851 = 192326
Step 227: 192326 + 851 = 193177
Step 228: 193177 + 851 = 194028
Step 229: 194028 + 851 = 194879
Step 230: 194879 + 851 = 195730
Step 231: 195730 + 851 = 196581
Step 232: 196581 + 851 = 197432
Step 233: 197432 + 851 = 198283
Step 234: 198283 + 851 = 199134
Step 235: 199134 + 851 = 199985
Step 236: 199985 + 851 = 200836
Step 237: 200836 + 851 = 201687
Step 238: 201687 + 851 = 202538
Step 239: 202538 + 851 = 203389
Step 240: 203389 + 851 = 204240
Step 241: 204240 + 851 = 205091
Step 242: 205091 + 851 = 205942
Step 243: 205942 + 851 = 206793
Step 244: 206793 + 851 = 207644
Step 245: 207644 + 851 = 208495
Step 246: 208495 + 851 = 209346
Step 247: 209346 + 851 = 210197
Step 248: 210197 + 851 = 211048
Step 249: 211048 + 851 = 211899
Step 250: 211899 + 851 = 212750
Step 251: 212750 + 851 = 213601
Step 252: 213601 + 851 = 214452
Step 253: 214452 + 851 = 215303
Step 254: 215303 + 851 = 216154
Step 255: 216154 + 851 = 217005
Step 256: 217005 + 851 = 217856
Step 257: 217856 + 851 = 218707
Step 258: 218707 + 851 = 219558
Step 259: 219558 + 851 = 220409
Step 260: 220409 + 851 = 221260
Step 261: 221260 + 851 = 222111
Step 262: 222111 + 851 = 222962
Step 263: 222962 + 851 = 223813
Step 264: 223813 + 851 = 224664
Step 265: 224664 + 851 = 225515
Step 266: 225515 + 851 = 226366
Step 267: 226366 + 851 = 227217
Step 268: 227217 + 851 = 228068
Step 269: 228068 + 851 = 228919
Step 270: 228919 + 851 = 229770
Step 271: 229770 + 851 = 230621
Step 272: 230621 + 851 = 231472
Step 273: 231472 + 851 = 232323
Step 274: 232323 + 851 = 233174
Step 275: 233174 + 851 = 234025
Step 276: 234025 + 851 = 234876
Step 277: 234876 + 851 = 235727
Step 278: 235727 + 851 = 236578
Step 279: 236578 + 851 = 237429
Step 280: 237429 + 851 = 238280
Step 281: 238280 + 851 = 239131
Step 282: 239131 + 851 = 239982
Step 283: 239982 + 851 = 240833
Step 284: 240833 + 851 = 241684
Step 285: 241684 + 851 = 242535
Step 286: 242535 + 851 = 243386
Step 287: 243386 + 851 = 244237
Step 288: 244237 + 851 = 245088
Step 289: 245088 + 851 = 245939
Step 290: 245939 + 851 = 246790
Step 291: 246790 + 851 = 247641
Step 292: 247641 + 851 = 248492
Step 293: 248492 + 851 = 249343
Step 294: 249343 + 851 = 250194
Step 295: 250194 + 851 = 251045
Step 296: 251045 + 851 = 251896
Step 297: 251896 + 851 = 252747
Step 298: 252747 + 851 = 253598
Step 299: 253598 + 851 = 254449
Step 300: 254449 + 851 = 255300
Step 301: 255300 + 851 = 256151
Step 302: 256151 + 851 = 257002
Step 303: 257002 + 851 = 257853
Step 304: 257853 + 851 = 258704
Step 305: 258704 + 851 = 259555
Step 306: 259555 + 851 = 260406
Step 307: 260406 + 851 = 261257
Step 308: 261257 + 851 = 262108
Step 309: 262108 + 851 = 262959
Step 310: 262959 + 851 = 263810
Step 311: 263810 + 851 = 264661
Step 312: 264661 + 851 = 265512
Step 313: 265512 + 851 = 266363
Step 314: 266363 + 851 = 267214
Step 315: 267214 + 851 = 268065
Step 316: 268065 + 851 = 268916
Step 317: 268916 + 851 = 269767
Step 318: 269767 + 851 = 270618
Step 319: 270618 + 851 = 271469
Step 320: 271469 + 851 = 272320
Step 321: 272320 + 851 = 273171
Step 322: 273171 + 851 = 274022
Step 323: 274022 + 851 = 274873
Step 324: 274873 + 851 = 275724
Step 325: 275724 + 851 = 276575
Step 326: 276575 + 851 = 277426
Step 327: 277426 + 851 = 278277
Step 328: 278277 + 851 = 279128
Step 329: 279128 + 851 = 279979
Step 330: 279979 + 851 = 280830
Step 331: 280830 + 851 = 281681
Step 332: 281681 + 851 = 282532
Step 333: 282532 + 851 = 283383
Step 334: 283383 + 851 = 284234
Step 335: 284234 + 851 = 285085
Step 336: 285085 + 851 = 285936
Step 337: 285936 + 851 = 286787
Step 338: 286787 + 851 = 287638
Step 339: 287638 + 851 = 288489
Step 340: 288489 + 851 = 289340
Step 341: 289340 + 851 = 290191
Step 342: 290191 + 851 = 291042
Step 343: 291042 + 851 = 291893
Step 344: 291893 + 851 = 292744
Step 345: 292744 + 851 = 293595
Step 346: 293595 + 851 = 294446
Step 347: 294446 + 851 = 295297
Step 348: 295297 + 851 = 296148
Step 349: 296148 + 851 = 296999
Step 350: 296999 + 851 = 297850
Step 351: 297850 + 851 = 298701
Step 352: 298701 + 851 = 299552
Step 353: 299552 + 851 = 300403
Step 354: 300403 + 851 = 301254
Step 355: 301254 + 851 = 302105
Step 356: 302105 + 851 = 302956
Step 357: 302956 + 851 = 303807

So, 851*357 = 303807