OK, let's crack this. We're given 804 and our task is to multiply it by 316. Essentially, we'll be adding 804 to itself 316 times.
Step 1: 0 + 804 = 804
Step 2: 804 + 804 = 1608
Step 3: 1608 + 804 = 2412
Step 4: 2412 + 804 = 3216
Step 5: 3216 + 804 = 4020
Step 6: 4020 + 804 = 4824
Step 7: 4824 + 804 = 5628
Step 8: 5628 + 804 = 6432
Step 9: 6432 + 804 = 7236
Step 10: 7236 + 804 = 8040
Step 11: 8040 + 804 = 8844
Step 12: 8844 + 804 = 9648
Step 13: 9648 + 804 = 10452
Step 14: 10452 + 804 = 11256
Step 15: 11256 + 804 = 12060
Step 16: 12060 + 804 = 12864
Step 17: 12864 + 804 = 13668
Step 18: 13668 + 804 = 14472
Step 19: 14472 + 804 = 15276
Step 20: 15276 + 804 = 16080
Step 21: 16080 + 804 = 16884
Step 22: 16884 + 804 = 17688
Step 23: 17688 + 804 = 18492
Step 24: 18492 + 804 = 19296
Step 25: 19296 + 804 = 20100
Step 26: 20100 + 804 = 20904
Step 27: 20904 + 804 = 21708
Step 28: 21708 + 804 = 22512
Step 29: 22512 + 804 = 23316
Step 30: 23316 + 804 = 24120
Step 31: 24120 + 804 = 24924
Step 32: 24924 + 804 = 25728
Step 33: 25728 + 804 = 26532
Step 34: 26532 + 804 = 27336
Step 35: 27336 + 804 = 28140
Step 36: 28140 + 804 = 28944
Step 37: 28944 + 804 = 29748
Step 38: 29748 + 804 = 30552
Step 39: 30552 + 804 = 31356
Step 40: 31356 + 804 = 32160
Step 41: 32160 + 804 = 32964
Step 42: 32964 + 804 = 33768
Step 43: 33768 + 804 = 34572
Step 44: 34572 + 804 = 35376
Step 45: 35376 + 804 = 36180
Step 46: 36180 + 804 = 36984
Step 47: 36984 + 804 = 37788
Step 48: 37788 + 804 = 38592
Step 49: 38592 + 804 = 39396
Step 50: 39396 + 804 = 40200
Step 51: 40200 + 804 = 41004
Step 52: 41004 + 804 = 41808
Step 53: 41808 + 804 = 42612
Step 54: 42612 + 804 = 43416
Step 55: 43416 + 804 = 44220
Step 56: 44220 + 804 = 45024
Step 57: 45024 + 804 = 45828
Step 58: 45828 + 804 = 46632
Step 59: 46632 + 804 = 47436
Step 60: 47436 + 804 = 48240
Step 61: 48240 + 804 = 49044
Step 62: 49044 + 804 = 49848
Step 63: 49848 + 804 = 50652
Step 64: 50652 + 804 = 51456
Step 65: 51456 + 804 = 52260
Step 66: 52260 + 804 = 53064
Step 67: 53064 + 804 = 53868
Step 68: 53868 + 804 = 54672
Step 69: 54672 + 804 = 55476
Step 70: 55476 + 804 = 56280
Step 71: 56280 + 804 = 57084
Step 72: 57084 + 804 = 57888
Step 73: 57888 + 804 = 58692
Step 74: 58692 + 804 = 59496
Step 75: 59496 + 804 = 60300
Step 76: 60300 + 804 = 61104
Step 77: 61104 + 804 = 61908
Step 78: 61908 + 804 = 62712
Step 79: 62712 + 804 = 63516
Step 80: 63516 + 804 = 64320
Step 81: 64320 + 804 = 65124
Step 82: 65124 + 804 = 65928
Step 83: 65928 + 804 = 66732
Step 84: 66732 + 804 = 67536
Step 85: 67536 + 804 = 68340
Step 86: 68340 + 804 = 69144
Step 87: 69144 + 804 = 69948
Step 88: 69948 + 804 = 70752
Step 89: 70752 + 804 = 71556
Step 90: 71556 + 804 = 72360
Step 91: 72360 + 804 = 73164
Step 92: 73164 + 804 = 73968
Step 93: 73968 + 804 = 74772
Step 94: 74772 + 804 = 75576
Step 95: 75576 + 804 = 76380
Step 96: 76380 + 804 = 77184
Step 97: 77184 + 804 = 77988
Step 98: 77988 + 804 = 78792
Step 99: 78792 + 804 = 79596
Step 100: 79596 + 804 = 80400
Step 101: 80400 + 804 = 81204
Step 102: 81204 + 804 = 82008
Step 103: 82008 + 804 = 82812
Step 104: 82812 + 804 = 83616
Step 105: 83616 + 804 = 84420
Step 106: 84420 + 804 = 85224
Step 107: 85224 + 804 = 86028
Step 108: 86028 + 804 = 86832
Step 109: 86832 + 804 = 87636
Step 110: 87636 + 804 = 88440
Step 111: 88440 + 804 = 89244
Step 112: 89244 + 804 = 90048
Step 113: 90048 + 804 = 90852
Step 114: 90852 + 804 = 91656
Step 115: 91656 + 804 = 92460
Step 116: 92460 + 804 = 93264
Step 117: 93264 + 804 = 94068
Step 118: 94068 + 804 = 94872
Step 119: 94872 + 804 = 95676
Step 120: 95676 + 804 = 96480
Step 121: 96480 + 804 = 97284
Step 122: 97284 + 804 = 98088
Step 123: 98088 + 804 = 98892
Step 124: 98892 + 804 = 99696
Step 125: 99696 + 804 = 100500
Step 126: 100500 + 804 = 101304
Step 127: 101304 + 804 = 102108
Step 128: 102108 + 804 = 102912
Step 129: 102912 + 804 = 103716
Step 130: 103716 + 804 = 104520
Step 131: 104520 + 804 = 105324
Step 132: 105324 + 804 = 106128
Step 133: 106128 + 804 = 106932
Step 134: 106932 + 804 = 107736
Step 135: 107736 + 804 = 108540
Step 136: 108540 + 804 = 109344
Step 137: 109344 + 804 = 110148
Step 138: 110148 + 804 = 110952
Step 139: 110952 + 804 = 111756
Step 140: 111756 + 804 = 112560
Step 141: 112560 + 804 = 113364
Step 142: 113364 + 804 = 114168
Step 143: 114168 + 804 = 114972
Step 144: 114972 + 804 = 115776
Step 145: 115776 + 804 = 116580
Step 146: 116580 + 804 = 117384
Step 147: 117384 + 804 = 118188
Step 148: 118188 + 804 = 118992
Step 149: 118992 + 804 = 119796
Step 150: 119796 + 804 = 120600
Step 151: 120600 + 804 = 121404
Step 152: 121404 + 804 = 122208
Step 153: 122208 + 804 = 123012
Step 154: 123012 + 804 = 123816
Step 155: 123816 + 804 = 124620
Step 156: 124620 + 804 = 125424
Step 157: 125424 + 804 = 126228
Step 158: 126228 + 804 = 127032
Step 159: 127032 + 804 = 127836
Step 160: 127836 + 804 = 128640
Step 161: 128640 + 804 = 129444
Step 162: 129444 + 804 = 130248
Step 163: 130248 + 804 = 131052
Step 164: 131052 + 804 = 131856
Step 165: 131856 + 804 = 132660
Step 166: 132660 + 804 = 133464
Step 167: 133464 + 804 = 134268
Step 168: 134268 + 804 = 135072
Step 169: 135072 + 804 = 135876
Step 170: 135876 + 804 = 136680
Step 171: 136680 + 804 = 137484
Step 172: 137484 + 804 = 138288
Step 173: 138288 + 804 = 139092
Step 174: 139092 + 804 = 139896
Step 175: 139896 + 804 = 140700
Step 176: 140700 + 804 = 141504
Step 177: 141504 + 804 = 142308
Step 178: 142308 + 804 = 143112
Step 179: 143112 + 804 = 143916
Step 180: 143916 + 804 = 144720
Step 181: 144720 + 804 = 145524
Step 182: 145524 + 804 = 146328
Step 183: 146328 + 804 = 147132
Step 184: 147132 + 804 = 147936
Step 185: 147936 + 804 = 148740
Step 186: 148740 + 804 = 149544
Step 187: 149544 + 804 = 150348
Step 188: 150348 + 804 = 151152
Step 189: 151152 + 804 = 151956
Step 190: 151956 + 804 = 152760
Step 191: 152760 + 804 = 153564
Step 192: 153564 + 804 = 154368
Step 193: 154368 + 804 = 155172
Step 194: 155172 + 804 = 155976
Step 195: 155976 + 804 = 156780
Step 196: 156780 + 804 = 157584
Step 197: 157584 + 804 = 158388
Step 198: 158388 + 804 = 159192
Step 199: 159192 + 804 = 159996
Step 200: 159996 + 804 = 160800
Step 201: 160800 + 804 = 161604
Step 202: 161604 + 804 = 162408
Step 203: 162408 + 804 = 163212
Step 204: 163212 + 804 = 164016
Step 205: 164016 + 804 = 164820
Step 206: 164820 + 804 = 165624
Step 207: 165624 + 804 = 166428
Step 208: 166428 + 804 = 167232
Step 209: 167232 + 804 = 168036
Step 210: 168036 + 804 = 168840
Step 211: 168840 + 804 = 169644
Step 212: 169644 + 804 = 170448
Step 213: 170448 + 804 = 171252
Step 214: 171252 + 804 = 172056
Step 215: 172056 + 804 = 172860
Step 216: 172860 + 804 = 173664
Step 217: 173664 + 804 = 174468
Step 218: 174468 + 804 = 175272
Step 219: 175272 + 804 = 176076
Step 220: 176076 + 804 = 176880
Step 221: 176880 + 804 = 177684
Step 222: 177684 + 804 = 178488
Step 223: 178488 + 804 = 179292
Step 224: 179292 + 804 = 180096
Step 225: 180096 + 804 = 180900
Step 226: 180900 + 804 = 181704
Step 227: 181704 + 804 = 182508
Step 228: 182508 + 804 = 183312
Step 229: 183312 + 804 = 184116
Step 230: 184116 + 804 = 184920
Step 231: 184920 + 804 = 185724
Step 232: 185724 + 804 = 186528
Step 233: 186528 + 804 = 187332
Step 234: 187332 + 804 = 188136
Step 235: 188136 + 804 = 188940
Step 236: 188940 + 804 = 189744
Step 237: 189744 + 804 = 190548
Step 238: 190548 + 804 = 191352
Step 239: 191352 + 804 = 192156
Step 240: 192156 + 804 = 192960
Step 241: 192960 + 804 = 193764
Step 242: 193764 + 804 = 194568
Step 243: 194568 + 804 = 195372
Step 244: 195372 + 804 = 196176
Step 245: 196176 + 804 = 196980
Step 246: 196980 + 804 = 197784
Step 247: 197784 + 804 = 198588
Step 248: 198588 + 804 = 199392
Step 249: 199392 + 804 = 200196
Step 250: 200196 + 804 = 201000
Step 251: 201000 + 804 = 201804
Step 252: 201804 + 804 = 202608
Step 253: 202608 + 804 = 203412
Step 254: 203412 + 804 = 204216
Step 255: 204216 + 804 = 205020
Step 256: 205020 + 804 = 205824
Step 257: 205824 + 804 = 206628
Step 258: 206628 + 804 = 207432
Step 259: 207432 + 804 = 208236
Step 260: 208236 + 804 = 209040
Step 261: 209040 + 804 = 209844
Step 262: 209844 + 804 = 210648
Step 263: 210648 + 804 = 211452
Step 264: 211452 + 804 = 212256
Step 265: 212256 + 804 = 213060
Step 266: 213060 + 804 = 213864
Step 267: 213864 + 804 = 214668
Step 268: 214668 + 804 = 215472
Step 269: 215472 + 804 = 216276
Step 270: 216276 + 804 = 217080
Step 271: 217080 + 804 = 217884
Step 272: 217884 + 804 = 218688
Step 273: 218688 + 804 = 219492
Step 274: 219492 + 804 = 220296
Step 275: 220296 + 804 = 221100
Step 276: 221100 + 804 = 221904
Step 277: 221904 + 804 = 222708
Step 278: 222708 + 804 = 223512
Step 279: 223512 + 804 = 224316
Step 280: 224316 + 804 = 225120
Step 281: 225120 + 804 = 225924
Step 282: 225924 + 804 = 226728
Step 283: 226728 + 804 = 227532
Step 284: 227532 + 804 = 228336
Step 285: 228336 + 804 = 229140
Step 286: 229140 + 804 = 229944
Step 287: 229944 + 804 = 230748
Step 288: 230748 + 804 = 231552
Step 289: 231552 + 804 = 232356
Step 290: 232356 + 804 = 233160
Step 291: 233160 + 804 = 233964
Step 292: 233964 + 804 = 234768
Step 293: 234768 + 804 = 235572
Step 294: 235572 + 804 = 236376
Step 295: 236376 + 804 = 237180
Step 296: 237180 + 804 = 237984
Step 297: 237984 + 804 = 238788
Step 298: 238788 + 804 = 239592
Step 299: 239592 + 804 = 240396
Step 300: 240396 + 804 = 241200
Step 301: 241200 + 804 = 242004
Step 302: 242004 + 804 = 242808
Step 303: 242808 + 804 = 243612
Step 304: 243612 + 804 = 244416
Step 305: 244416 + 804 = 245220
Step 306: 245220 + 804 = 246024
Step 307: 246024 + 804 = 246828
Step 308: 246828 + 804 = 247632
Step 309: 247632 + 804 = 248436
Step 310: 248436 + 804 = 249240
Step 311: 249240 + 804 = 250044
Step 312: 250044 + 804 = 250848
Step 313: 250848 + 804 = 251652
Step 314: 251652 + 804 = 252456
Step 315: 252456 + 804 = 253260
Step 316: 253260 + 804 = 254064

So, 804*316 = 254064