OK, let's crack this. We're given 811 and our task is to multiply it by 342. Essentially, we'll be adding 811 to itself 342 times.
Step 1: 0 + 811 = 811
Step 2: 811 + 811 = 1622
Step 3: 1622 + 811 = 2433
Step 4: 2433 + 811 = 3244
Step 5: 3244 + 811 = 4055
Step 6: 4055 + 811 = 4866
Step 7: 4866 + 811 = 5677
Step 8: 5677 + 811 = 6488
Step 9: 6488 + 811 = 7299
Step 10: 7299 + 811 = 8110
Step 11: 8110 + 811 = 8921
Step 12: 8921 + 811 = 9732
Step 13: 9732 + 811 = 10543
Step 14: 10543 + 811 = 11354
Step 15: 11354 + 811 = 12165
Step 16: 12165 + 811 = 12976
Step 17: 12976 + 811 = 13787
Step 18: 13787 + 811 = 14598
Step 19: 14598 + 811 = 15409
Step 20: 15409 + 811 = 16220
Step 21: 16220 + 811 = 17031
Step 22: 17031 + 811 = 17842
Step 23: 17842 + 811 = 18653
Step 24: 18653 + 811 = 19464
Step 25: 19464 + 811 = 20275
Step 26: 20275 + 811 = 21086
Step 27: 21086 + 811 = 21897
Step 28: 21897 + 811 = 22708
Step 29: 22708 + 811 = 23519
Step 30: 23519 + 811 = 24330
Step 31: 24330 + 811 = 25141
Step 32: 25141 + 811 = 25952
Step 33: 25952 + 811 = 26763
Step 34: 26763 + 811 = 27574
Step 35: 27574 + 811 = 28385
Step 36: 28385 + 811 = 29196
Step 37: 29196 + 811 = 30007
Step 38: 30007 + 811 = 30818
Step 39: 30818 + 811 = 31629
Step 40: 31629 + 811 = 32440
Step 41: 32440 + 811 = 33251
Step 42: 33251 + 811 = 34062
Step 43: 34062 + 811 = 34873
Step 44: 34873 + 811 = 35684
Step 45: 35684 + 811 = 36495
Step 46: 36495 + 811 = 37306
Step 47: 37306 + 811 = 38117
Step 48: 38117 + 811 = 38928
Step 49: 38928 + 811 = 39739
Step 50: 39739 + 811 = 40550
Step 51: 40550 + 811 = 41361
Step 52: 41361 + 811 = 42172
Step 53: 42172 + 811 = 42983
Step 54: 42983 + 811 = 43794
Step 55: 43794 + 811 = 44605
Step 56: 44605 + 811 = 45416
Step 57: 45416 + 811 = 46227
Step 58: 46227 + 811 = 47038
Step 59: 47038 + 811 = 47849
Step 60: 47849 + 811 = 48660
Step 61: 48660 + 811 = 49471
Step 62: 49471 + 811 = 50282
Step 63: 50282 + 811 = 51093
Step 64: 51093 + 811 = 51904
Step 65: 51904 + 811 = 52715
Step 66: 52715 + 811 = 53526
Step 67: 53526 + 811 = 54337
Step 68: 54337 + 811 = 55148
Step 69: 55148 + 811 = 55959
Step 70: 55959 + 811 = 56770
Step 71: 56770 + 811 = 57581
Step 72: 57581 + 811 = 58392
Step 73: 58392 + 811 = 59203
Step 74: 59203 + 811 = 60014
Step 75: 60014 + 811 = 60825
Step 76: 60825 + 811 = 61636
Step 77: 61636 + 811 = 62447
Step 78: 62447 + 811 = 63258
Step 79: 63258 + 811 = 64069
Step 80: 64069 + 811 = 64880
Step 81: 64880 + 811 = 65691
Step 82: 65691 + 811 = 66502
Step 83: 66502 + 811 = 67313
Step 84: 67313 + 811 = 68124
Step 85: 68124 + 811 = 68935
Step 86: 68935 + 811 = 69746
Step 87: 69746 + 811 = 70557
Step 88: 70557 + 811 = 71368
Step 89: 71368 + 811 = 72179
Step 90: 72179 + 811 = 72990
Step 91: 72990 + 811 = 73801
Step 92: 73801 + 811 = 74612
Step 93: 74612 + 811 = 75423
Step 94: 75423 + 811 = 76234
Step 95: 76234 + 811 = 77045
Step 96: 77045 + 811 = 77856
Step 97: 77856 + 811 = 78667
Step 98: 78667 + 811 = 79478
Step 99: 79478 + 811 = 80289
Step 100: 80289 + 811 = 81100
Step 101: 81100 + 811 = 81911
Step 102: 81911 + 811 = 82722
Step 103: 82722 + 811 = 83533
Step 104: 83533 + 811 = 84344
Step 105: 84344 + 811 = 85155
Step 106: 85155 + 811 = 85966
Step 107: 85966 + 811 = 86777
Step 108: 86777 + 811 = 87588
Step 109: 87588 + 811 = 88399
Step 110: 88399 + 811 = 89210
Step 111: 89210 + 811 = 90021
Step 112: 90021 + 811 = 90832
Step 113: 90832 + 811 = 91643
Step 114: 91643 + 811 = 92454
Step 115: 92454 + 811 = 93265
Step 116: 93265 + 811 = 94076
Step 117: 94076 + 811 = 94887
Step 118: 94887 + 811 = 95698
Step 119: 95698 + 811 = 96509
Step 120: 96509 + 811 = 97320
Step 121: 97320 + 811 = 98131
Step 122: 98131 + 811 = 98942
Step 123: 98942 + 811 = 99753
Step 124: 99753 + 811 = 100564
Step 125: 100564 + 811 = 101375
Step 126: 101375 + 811 = 102186
Step 127: 102186 + 811 = 102997
Step 128: 102997 + 811 = 103808
Step 129: 103808 + 811 = 104619
Step 130: 104619 + 811 = 105430
Step 131: 105430 + 811 = 106241
Step 132: 106241 + 811 = 107052
Step 133: 107052 + 811 = 107863
Step 134: 107863 + 811 = 108674
Step 135: 108674 + 811 = 109485
Step 136: 109485 + 811 = 110296
Step 137: 110296 + 811 = 111107
Step 138: 111107 + 811 = 111918
Step 139: 111918 + 811 = 112729
Step 140: 112729 + 811 = 113540
Step 141: 113540 + 811 = 114351
Step 142: 114351 + 811 = 115162
Step 143: 115162 + 811 = 115973
Step 144: 115973 + 811 = 116784
Step 145: 116784 + 811 = 117595
Step 146: 117595 + 811 = 118406
Step 147: 118406 + 811 = 119217
Step 148: 119217 + 811 = 120028
Step 149: 120028 + 811 = 120839
Step 150: 120839 + 811 = 121650
Step 151: 121650 + 811 = 122461
Step 152: 122461 + 811 = 123272
Step 153: 123272 + 811 = 124083
Step 154: 124083 + 811 = 124894
Step 155: 124894 + 811 = 125705
Step 156: 125705 + 811 = 126516
Step 157: 126516 + 811 = 127327
Step 158: 127327 + 811 = 128138
Step 159: 128138 + 811 = 128949
Step 160: 128949 + 811 = 129760
Step 161: 129760 + 811 = 130571
Step 162: 130571 + 811 = 131382
Step 163: 131382 + 811 = 132193
Step 164: 132193 + 811 = 133004
Step 165: 133004 + 811 = 133815
Step 166: 133815 + 811 = 134626
Step 167: 134626 + 811 = 135437
Step 168: 135437 + 811 = 136248
Step 169: 136248 + 811 = 137059
Step 170: 137059 + 811 = 137870
Step 171: 137870 + 811 = 138681
Step 172: 138681 + 811 = 139492
Step 173: 139492 + 811 = 140303
Step 174: 140303 + 811 = 141114
Step 175: 141114 + 811 = 141925
Step 176: 141925 + 811 = 142736
Step 177: 142736 + 811 = 143547
Step 178: 143547 + 811 = 144358
Step 179: 144358 + 811 = 145169
Step 180: 145169 + 811 = 145980
Step 181: 145980 + 811 = 146791
Step 182: 146791 + 811 = 147602
Step 183: 147602 + 811 = 148413
Step 184: 148413 + 811 = 149224
Step 185: 149224 + 811 = 150035
Step 186: 150035 + 811 = 150846
Step 187: 150846 + 811 = 151657
Step 188: 151657 + 811 = 152468
Step 189: 152468 + 811 = 153279
Step 190: 153279 + 811 = 154090
Step 191: 154090 + 811 = 154901
Step 192: 154901 + 811 = 155712
Step 193: 155712 + 811 = 156523
Step 194: 156523 + 811 = 157334
Step 195: 157334 + 811 = 158145
Step 196: 158145 + 811 = 158956
Step 197: 158956 + 811 = 159767
Step 198: 159767 + 811 = 160578
Step 199: 160578 + 811 = 161389
Step 200: 161389 + 811 = 162200
Step 201: 162200 + 811 = 163011
Step 202: 163011 + 811 = 163822
Step 203: 163822 + 811 = 164633
Step 204: 164633 + 811 = 165444
Step 205: 165444 + 811 = 166255
Step 206: 166255 + 811 = 167066
Step 207: 167066 + 811 = 167877
Step 208: 167877 + 811 = 168688
Step 209: 168688 + 811 = 169499
Step 210: 169499 + 811 = 170310
Step 211: 170310 + 811 = 171121
Step 212: 171121 + 811 = 171932
Step 213: 171932 + 811 = 172743
Step 214: 172743 + 811 = 173554
Step 215: 173554 + 811 = 174365
Step 216: 174365 + 811 = 175176
Step 217: 175176 + 811 = 175987
Step 218: 175987 + 811 = 176798
Step 219: 176798 + 811 = 177609
Step 220: 177609 + 811 = 178420
Step 221: 178420 + 811 = 179231
Step 222: 179231 + 811 = 180042
Step 223: 180042 + 811 = 180853
Step 224: 180853 + 811 = 181664
Step 225: 181664 + 811 = 182475
Step 226: 182475 + 811 = 183286
Step 227: 183286 + 811 = 184097
Step 228: 184097 + 811 = 184908
Step 229: 184908 + 811 = 185719
Step 230: 185719 + 811 = 186530
Step 231: 186530 + 811 = 187341
Step 232: 187341 + 811 = 188152
Step 233: 188152 + 811 = 188963
Step 234: 188963 + 811 = 189774
Step 235: 189774 + 811 = 190585
Step 236: 190585 + 811 = 191396
Step 237: 191396 + 811 = 192207
Step 238: 192207 + 811 = 193018
Step 239: 193018 + 811 = 193829
Step 240: 193829 + 811 = 194640
Step 241: 194640 + 811 = 195451
Step 242: 195451 + 811 = 196262
Step 243: 196262 + 811 = 197073
Step 244: 197073 + 811 = 197884
Step 245: 197884 + 811 = 198695
Step 246: 198695 + 811 = 199506
Step 247: 199506 + 811 = 200317
Step 248: 200317 + 811 = 201128
Step 249: 201128 + 811 = 201939
Step 250: 201939 + 811 = 202750
Step 251: 202750 + 811 = 203561
Step 252: 203561 + 811 = 204372
Step 253: 204372 + 811 = 205183
Step 254: 205183 + 811 = 205994
Step 255: 205994 + 811 = 206805
Step 256: 206805 + 811 = 207616
Step 257: 207616 + 811 = 208427
Step 258: 208427 + 811 = 209238
Step 259: 209238 + 811 = 210049
Step 260: 210049 + 811 = 210860
Step 261: 210860 + 811 = 211671
Step 262: 211671 + 811 = 212482
Step 263: 212482 + 811 = 213293
Step 264: 213293 + 811 = 214104
Step 265: 214104 + 811 = 214915
Step 266: 214915 + 811 = 215726
Step 267: 215726 + 811 = 216537
Step 268: 216537 + 811 = 217348
Step 269: 217348 + 811 = 218159
Step 270: 218159 + 811 = 218970
Step 271: 218970 + 811 = 219781
Step 272: 219781 + 811 = 220592
Step 273: 220592 + 811 = 221403
Step 274: 221403 + 811 = 222214
Step 275: 222214 + 811 = 223025
Step 276: 223025 + 811 = 223836
Step 277: 223836 + 811 = 224647
Step 278: 224647 + 811 = 225458
Step 279: 225458 + 811 = 226269
Step 280: 226269 + 811 = 227080
Step 281: 227080 + 811 = 227891
Step 282: 227891 + 811 = 228702
Step 283: 228702 + 811 = 229513
Step 284: 229513 + 811 = 230324
Step 285: 230324 + 811 = 231135
Step 286: 231135 + 811 = 231946
Step 287: 231946 + 811 = 232757
Step 288: 232757 + 811 = 233568
Step 289: 233568 + 811 = 234379
Step 290: 234379 + 811 = 235190
Step 291: 235190 + 811 = 236001
Step 292: 236001 + 811 = 236812
Step 293: 236812 + 811 = 237623
Step 294: 237623 + 811 = 238434
Step 295: 238434 + 811 = 239245
Step 296: 239245 + 811 = 240056
Step 297: 240056 + 811 = 240867
Step 298: 240867 + 811 = 241678
Step 299: 241678 + 811 = 242489
Step 300: 242489 + 811 = 243300
Step 301: 243300 + 811 = 244111
Step 302: 244111 + 811 = 244922
Step 303: 244922 + 811 = 245733
Step 304: 245733 + 811 = 246544
Step 305: 246544 + 811 = 247355
Step 306: 247355 + 811 = 248166
Step 307: 248166 + 811 = 248977
Step 308: 248977 + 811 = 249788
Step 309: 249788 + 811 = 250599
Step 310: 250599 + 811 = 251410
Step 311: 251410 + 811 = 252221
Step 312: 252221 + 811 = 253032
Step 313: 253032 + 811 = 253843
Step 314: 253843 + 811 = 254654
Step 315: 254654 + 811 = 255465
Step 316: 255465 + 811 = 256276
Step 317: 256276 + 811 = 257087
Step 318: 257087 + 811 = 257898
Step 319: 257898 + 811 = 258709
Step 320: 258709 + 811 = 259520
Step 321: 259520 + 811 = 260331
Step 322: 260331 + 811 = 261142
Step 323: 261142 + 811 = 261953
Step 324: 261953 + 811 = 262764
Step 325: 262764 + 811 = 263575
Step 326: 263575 + 811 = 264386
Step 327: 264386 + 811 = 265197
Step 328: 265197 + 811 = 266008
Step 329: 266008 + 811 = 266819
Step 330: 266819 + 811 = 267630
Step 331: 267630 + 811 = 268441
Step 332: 268441 + 811 = 269252
Step 333: 269252 + 811 = 270063
Step 334: 270063 + 811 = 270874
Step 335: 270874 + 811 = 271685
Step 336: 271685 + 811 = 272496
Step 337: 272496 + 811 = 273307
Step 338: 273307 + 811 = 274118
Step 339: 274118 + 811 = 274929
Step 340: 274929 + 811 = 275740
Step 341: 275740 + 811 = 276551
Step 342: 276551 + 811 = 277362

So, 811*342 = 277362