OK, let's crack this. We're given 781 and our task is to multiply it by 319. Essentially, we'll be adding 781 to itself 319 times.
Step 1: 0 + 781 = 781
Step 2: 781 + 781 = 1562
Step 3: 1562 + 781 = 2343
Step 4: 2343 + 781 = 3124
Step 5: 3124 + 781 = 3905
Step 6: 3905 + 781 = 4686
Step 7: 4686 + 781 = 5467
Step 8: 5467 + 781 = 6248
Step 9: 6248 + 781 = 7029
Step 10: 7029 + 781 = 7810
Step 11: 7810 + 781 = 8591
Step 12: 8591 + 781 = 9372
Step 13: 9372 + 781 = 10153
Step 14: 10153 + 781 = 10934
Step 15: 10934 + 781 = 11715
Step 16: 11715 + 781 = 12496
Step 17: 12496 + 781 = 13277
Step 18: 13277 + 781 = 14058
Step 19: 14058 + 781 = 14839
Step 20: 14839 + 781 = 15620
Step 21: 15620 + 781 = 16401
Step 22: 16401 + 781 = 17182
Step 23: 17182 + 781 = 17963
Step 24: 17963 + 781 = 18744
Step 25: 18744 + 781 = 19525
Step 26: 19525 + 781 = 20306
Step 27: 20306 + 781 = 21087
Step 28: 21087 + 781 = 21868
Step 29: 21868 + 781 = 22649
Step 30: 22649 + 781 = 23430
Step 31: 23430 + 781 = 24211
Step 32: 24211 + 781 = 24992
Step 33: 24992 + 781 = 25773
Step 34: 25773 + 781 = 26554
Step 35: 26554 + 781 = 27335
Step 36: 27335 + 781 = 28116
Step 37: 28116 + 781 = 28897
Step 38: 28897 + 781 = 29678
Step 39: 29678 + 781 = 30459
Step 40: 30459 + 781 = 31240
Step 41: 31240 + 781 = 32021
Step 42: 32021 + 781 = 32802
Step 43: 32802 + 781 = 33583
Step 44: 33583 + 781 = 34364
Step 45: 34364 + 781 = 35145
Step 46: 35145 + 781 = 35926
Step 47: 35926 + 781 = 36707
Step 48: 36707 + 781 = 37488
Step 49: 37488 + 781 = 38269
Step 50: 38269 + 781 = 39050
Step 51: 39050 + 781 = 39831
Step 52: 39831 + 781 = 40612
Step 53: 40612 + 781 = 41393
Step 54: 41393 + 781 = 42174
Step 55: 42174 + 781 = 42955
Step 56: 42955 + 781 = 43736
Step 57: 43736 + 781 = 44517
Step 58: 44517 + 781 = 45298
Step 59: 45298 + 781 = 46079
Step 60: 46079 + 781 = 46860
Step 61: 46860 + 781 = 47641
Step 62: 47641 + 781 = 48422
Step 63: 48422 + 781 = 49203
Step 64: 49203 + 781 = 49984
Step 65: 49984 + 781 = 50765
Step 66: 50765 + 781 = 51546
Step 67: 51546 + 781 = 52327
Step 68: 52327 + 781 = 53108
Step 69: 53108 + 781 = 53889
Step 70: 53889 + 781 = 54670
Step 71: 54670 + 781 = 55451
Step 72: 55451 + 781 = 56232
Step 73: 56232 + 781 = 57013
Step 74: 57013 + 781 = 57794
Step 75: 57794 + 781 = 58575
Step 76: 58575 + 781 = 59356
Step 77: 59356 + 781 = 60137
Step 78: 60137 + 781 = 60918
Step 79: 60918 + 781 = 61699
Step 80: 61699 + 781 = 62480
Step 81: 62480 + 781 = 63261
Step 82: 63261 + 781 = 64042
Step 83: 64042 + 781 = 64823
Step 84: 64823 + 781 = 65604
Step 85: 65604 + 781 = 66385
Step 86: 66385 + 781 = 67166
Step 87: 67166 + 781 = 67947
Step 88: 67947 + 781 = 68728
Step 89: 68728 + 781 = 69509
Step 90: 69509 + 781 = 70290
Step 91: 70290 + 781 = 71071
Step 92: 71071 + 781 = 71852
Step 93: 71852 + 781 = 72633
Step 94: 72633 + 781 = 73414
Step 95: 73414 + 781 = 74195
Step 96: 74195 + 781 = 74976
Step 97: 74976 + 781 = 75757
Step 98: 75757 + 781 = 76538
Step 99: 76538 + 781 = 77319
Step 100: 77319 + 781 = 78100
Step 101: 78100 + 781 = 78881
Step 102: 78881 + 781 = 79662
Step 103: 79662 + 781 = 80443
Step 104: 80443 + 781 = 81224
Step 105: 81224 + 781 = 82005
Step 106: 82005 + 781 = 82786
Step 107: 82786 + 781 = 83567
Step 108: 83567 + 781 = 84348
Step 109: 84348 + 781 = 85129
Step 110: 85129 + 781 = 85910
Step 111: 85910 + 781 = 86691
Step 112: 86691 + 781 = 87472
Step 113: 87472 + 781 = 88253
Step 114: 88253 + 781 = 89034
Step 115: 89034 + 781 = 89815
Step 116: 89815 + 781 = 90596
Step 117: 90596 + 781 = 91377
Step 118: 91377 + 781 = 92158
Step 119: 92158 + 781 = 92939
Step 120: 92939 + 781 = 93720
Step 121: 93720 + 781 = 94501
Step 122: 94501 + 781 = 95282
Step 123: 95282 + 781 = 96063
Step 124: 96063 + 781 = 96844
Step 125: 96844 + 781 = 97625
Step 126: 97625 + 781 = 98406
Step 127: 98406 + 781 = 99187
Step 128: 99187 + 781 = 99968
Step 129: 99968 + 781 = 100749
Step 130: 100749 + 781 = 101530
Step 131: 101530 + 781 = 102311
Step 132: 102311 + 781 = 103092
Step 133: 103092 + 781 = 103873
Step 134: 103873 + 781 = 104654
Step 135: 104654 + 781 = 105435
Step 136: 105435 + 781 = 106216
Step 137: 106216 + 781 = 106997
Step 138: 106997 + 781 = 107778
Step 139: 107778 + 781 = 108559
Step 140: 108559 + 781 = 109340
Step 141: 109340 + 781 = 110121
Step 142: 110121 + 781 = 110902
Step 143: 110902 + 781 = 111683
Step 144: 111683 + 781 = 112464
Step 145: 112464 + 781 = 113245
Step 146: 113245 + 781 = 114026
Step 147: 114026 + 781 = 114807
Step 148: 114807 + 781 = 115588
Step 149: 115588 + 781 = 116369
Step 150: 116369 + 781 = 117150
Step 151: 117150 + 781 = 117931
Step 152: 117931 + 781 = 118712
Step 153: 118712 + 781 = 119493
Step 154: 119493 + 781 = 120274
Step 155: 120274 + 781 = 121055
Step 156: 121055 + 781 = 121836
Step 157: 121836 + 781 = 122617
Step 158: 122617 + 781 = 123398
Step 159: 123398 + 781 = 124179
Step 160: 124179 + 781 = 124960
Step 161: 124960 + 781 = 125741
Step 162: 125741 + 781 = 126522
Step 163: 126522 + 781 = 127303
Step 164: 127303 + 781 = 128084
Step 165: 128084 + 781 = 128865
Step 166: 128865 + 781 = 129646
Step 167: 129646 + 781 = 130427
Step 168: 130427 + 781 = 131208
Step 169: 131208 + 781 = 131989
Step 170: 131989 + 781 = 132770
Step 171: 132770 + 781 = 133551
Step 172: 133551 + 781 = 134332
Step 173: 134332 + 781 = 135113
Step 174: 135113 + 781 = 135894
Step 175: 135894 + 781 = 136675
Step 176: 136675 + 781 = 137456
Step 177: 137456 + 781 = 138237
Step 178: 138237 + 781 = 139018
Step 179: 139018 + 781 = 139799
Step 180: 139799 + 781 = 140580
Step 181: 140580 + 781 = 141361
Step 182: 141361 + 781 = 142142
Step 183: 142142 + 781 = 142923
Step 184: 142923 + 781 = 143704
Step 185: 143704 + 781 = 144485
Step 186: 144485 + 781 = 145266
Step 187: 145266 + 781 = 146047
Step 188: 146047 + 781 = 146828
Step 189: 146828 + 781 = 147609
Step 190: 147609 + 781 = 148390
Step 191: 148390 + 781 = 149171
Step 192: 149171 + 781 = 149952
Step 193: 149952 + 781 = 150733
Step 194: 150733 + 781 = 151514
Step 195: 151514 + 781 = 152295
Step 196: 152295 + 781 = 153076
Step 197: 153076 + 781 = 153857
Step 198: 153857 + 781 = 154638
Step 199: 154638 + 781 = 155419
Step 200: 155419 + 781 = 156200
Step 201: 156200 + 781 = 156981
Step 202: 156981 + 781 = 157762
Step 203: 157762 + 781 = 158543
Step 204: 158543 + 781 = 159324
Step 205: 159324 + 781 = 160105
Step 206: 160105 + 781 = 160886
Step 207: 160886 + 781 = 161667
Step 208: 161667 + 781 = 162448
Step 209: 162448 + 781 = 163229
Step 210: 163229 + 781 = 164010
Step 211: 164010 + 781 = 164791
Step 212: 164791 + 781 = 165572
Step 213: 165572 + 781 = 166353
Step 214: 166353 + 781 = 167134
Step 215: 167134 + 781 = 167915
Step 216: 167915 + 781 = 168696
Step 217: 168696 + 781 = 169477
Step 218: 169477 + 781 = 170258
Step 219: 170258 + 781 = 171039
Step 220: 171039 + 781 = 171820
Step 221: 171820 + 781 = 172601
Step 222: 172601 + 781 = 173382
Step 223: 173382 + 781 = 174163
Step 224: 174163 + 781 = 174944
Step 225: 174944 + 781 = 175725
Step 226: 175725 + 781 = 176506
Step 227: 176506 + 781 = 177287
Step 228: 177287 + 781 = 178068
Step 229: 178068 + 781 = 178849
Step 230: 178849 + 781 = 179630
Step 231: 179630 + 781 = 180411
Step 232: 180411 + 781 = 181192
Step 233: 181192 + 781 = 181973
Step 234: 181973 + 781 = 182754
Step 235: 182754 + 781 = 183535
Step 236: 183535 + 781 = 184316
Step 237: 184316 + 781 = 185097
Step 238: 185097 + 781 = 185878
Step 239: 185878 + 781 = 186659
Step 240: 186659 + 781 = 187440
Step 241: 187440 + 781 = 188221
Step 242: 188221 + 781 = 189002
Step 243: 189002 + 781 = 189783
Step 244: 189783 + 781 = 190564
Step 245: 190564 + 781 = 191345
Step 246: 191345 + 781 = 192126
Step 247: 192126 + 781 = 192907
Step 248: 192907 + 781 = 193688
Step 249: 193688 + 781 = 194469
Step 250: 194469 + 781 = 195250
Step 251: 195250 + 781 = 196031
Step 252: 196031 + 781 = 196812
Step 253: 196812 + 781 = 197593
Step 254: 197593 + 781 = 198374
Step 255: 198374 + 781 = 199155
Step 256: 199155 + 781 = 199936
Step 257: 199936 + 781 = 200717
Step 258: 200717 + 781 = 201498
Step 259: 201498 + 781 = 202279
Step 260: 202279 + 781 = 203060
Step 261: 203060 + 781 = 203841
Step 262: 203841 + 781 = 204622
Step 263: 204622 + 781 = 205403
Step 264: 205403 + 781 = 206184
Step 265: 206184 + 781 = 206965
Step 266: 206965 + 781 = 207746
Step 267: 207746 + 781 = 208527
Step 268: 208527 + 781 = 209308
Step 269: 209308 + 781 = 210089
Step 270: 210089 + 781 = 210870
Step 271: 210870 + 781 = 211651
Step 272: 211651 + 781 = 212432
Step 273: 212432 + 781 = 213213
Step 274: 213213 + 781 = 213994
Step 275: 213994 + 781 = 214775
Step 276: 214775 + 781 = 215556
Step 277: 215556 + 781 = 216337
Step 278: 216337 + 781 = 217118
Step 279: 217118 + 781 = 217899
Step 280: 217899 + 781 = 218680
Step 281: 218680 + 781 = 219461
Step 282: 219461 + 781 = 220242
Step 283: 220242 + 781 = 221023
Step 284: 221023 + 781 = 221804
Step 285: 221804 + 781 = 222585
Step 286: 222585 + 781 = 223366
Step 287: 223366 + 781 = 224147
Step 288: 224147 + 781 = 224928
Step 289: 224928 + 781 = 225709
Step 290: 225709 + 781 = 226490
Step 291: 226490 + 781 = 227271
Step 292: 227271 + 781 = 228052
Step 293: 228052 + 781 = 228833
Step 294: 228833 + 781 = 229614
Step 295: 229614 + 781 = 230395
Step 296: 230395 + 781 = 231176
Step 297: 231176 + 781 = 231957
Step 298: 231957 + 781 = 232738
Step 299: 232738 + 781 = 233519
Step 300: 233519 + 781 = 234300
Step 301: 234300 + 781 = 235081
Step 302: 235081 + 781 = 235862
Step 303: 235862 + 781 = 236643
Step 304: 236643 + 781 = 237424
Step 305: 237424 + 781 = 238205
Step 306: 238205 + 781 = 238986
Step 307: 238986 + 781 = 239767
Step 308: 239767 + 781 = 240548
Step 309: 240548 + 781 = 241329
Step 310: 241329 + 781 = 242110
Step 311: 242110 + 781 = 242891
Step 312: 242891 + 781 = 243672
Step 313: 243672 + 781 = 244453
Step 314: 244453 + 781 = 245234
Step 315: 245234 + 781 = 246015
Step 316: 246015 + 781 = 246796
Step 317: 246796 + 781 = 247577
Step 318: 247577 + 781 = 248358
Step 319: 248358 + 781 = 249139

So, 781*319 = 249139