Alright, let's solve this math problem step by step. First, we have the number 905. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 143. So, we're going to take the number 905 and add it to itself 143 times.
Step 1: 0 + 905 = 905
Step 2: 905 + 905 = 1810
Step 3: 1810 + 905 = 2715
Step 4: 2715 + 905 = 3620
Step 5: 3620 + 905 = 4525
Step 6: 4525 + 905 = 5430
Step 7: 5430 + 905 = 6335
Step 8: 6335 + 905 = 7240
Step 9: 7240 + 905 = 8145
Step 10: 8145 + 905 = 9050
Step 11: 9050 + 905 = 9955
Step 12: 9955 + 905 = 10860
Step 13: 10860 + 905 = 11765
Step 14: 11765 + 905 = 12670
Step 15: 12670 + 905 = 13575
Step 16: 13575 + 905 = 14480
Step 17: 14480 + 905 = 15385
Step 18: 15385 + 905 = 16290
Step 19: 16290 + 905 = 17195
Step 20: 17195 + 905 = 18100
Step 21: 18100 + 905 = 19005
Step 22: 19005 + 905 = 19910
Step 23: 19910 + 905 = 20815
Step 24: 20815 + 905 = 21720
Step 25: 21720 + 905 = 22625
Step 26: 22625 + 905 = 23530
Step 27: 23530 + 905 = 24435
Step 28: 24435 + 905 = 25340
Step 29: 25340 + 905 = 26245
Step 30: 26245 + 905 = 27150
Step 31: 27150 + 905 = 28055
Step 32: 28055 + 905 = 28960
Step 33: 28960 + 905 = 29865
Step 34: 29865 + 905 = 30770
Step 35: 30770 + 905 = 31675
Step 36: 31675 + 905 = 32580
Step 37: 32580 + 905 = 33485
Step 38: 33485 + 905 = 34390
Step 39: 34390 + 905 = 35295
Step 40: 35295 + 905 = 36200
Step 41: 36200 + 905 = 37105
Step 42: 37105 + 905 = 38010
Step 43: 38010 + 905 = 38915
Step 44: 38915 + 905 = 39820
Step 45: 39820 + 905 = 40725
Step 46: 40725 + 905 = 41630
Step 47: 41630 + 905 = 42535
Step 48: 42535 + 905 = 43440
Step 49: 43440 + 905 = 44345
Step 50: 44345 + 905 = 45250
Step 51: 45250 + 905 = 46155
Step 52: 46155 + 905 = 47060
Step 53: 47060 + 905 = 47965
Step 54: 47965 + 905 = 48870
Step 55: 48870 + 905 = 49775
Step 56: 49775 + 905 = 50680
Step 57: 50680 + 905 = 51585
Step 58: 51585 + 905 = 52490
Step 59: 52490 + 905 = 53395
Step 60: 53395 + 905 = 54300
Step 61: 54300 + 905 = 55205
Step 62: 55205 + 905 = 56110
Step 63: 56110 + 905 = 57015
Step 64: 57015 + 905 = 57920
Step 65: 57920 + 905 = 58825
Step 66: 58825 + 905 = 59730
Step 67: 59730 + 905 = 60635
Step 68: 60635 + 905 = 61540
Step 69: 61540 + 905 = 62445
Step 70: 62445 + 905 = 63350
Step 71: 63350 + 905 = 64255
Step 72: 64255 + 905 = 65160
Step 73: 65160 + 905 = 66065
Step 74: 66065 + 905 = 66970
Step 75: 66970 + 905 = 67875
Step 76: 67875 + 905 = 68780
Step 77: 68780 + 905 = 69685
Step 78: 69685 + 905 = 70590
Step 79: 70590 + 905 = 71495
Step 80: 71495 + 905 = 72400
Step 81: 72400 + 905 = 73305
Step 82: 73305 + 905 = 74210
Step 83: 74210 + 905 = 75115
Step 84: 75115 + 905 = 76020
Step 85: 76020 + 905 = 76925
Step 86: 76925 + 905 = 77830
Step 87: 77830 + 905 = 78735
Step 88: 78735 + 905 = 79640
Step 89: 79640 + 905 = 80545
Step 90: 80545 + 905 = 81450
Step 91: 81450 + 905 = 82355
Step 92: 82355 + 905 = 83260
Step 93: 83260 + 905 = 84165
Step 94: 84165 + 905 = 85070
Step 95: 85070 + 905 = 85975
Step 96: 85975 + 905 = 86880
Step 97: 86880 + 905 = 87785
Step 98: 87785 + 905 = 88690
Step 99: 88690 + 905 = 89595
Step 100: 89595 + 905 = 90500
Step 101: 90500 + 905 = 91405
Step 102: 91405 + 905 = 92310
Step 103: 92310 + 905 = 93215
Step 104: 93215 + 905 = 94120
Step 105: 94120 + 905 = 95025
Step 106: 95025 + 905 = 95930
Step 107: 95930 + 905 = 96835
Step 108: 96835 + 905 = 97740
Step 109: 97740 + 905 = 98645
Step 110: 98645 + 905 = 99550
Step 111: 99550 + 905 = 100455
Step 112: 100455 + 905 = 101360
Step 113: 101360 + 905 = 102265
Step 114: 102265 + 905 = 103170
Step 115: 103170 + 905 = 104075
Step 116: 104075 + 905 = 104980
Step 117: 104980 + 905 = 105885
Step 118: 105885 + 905 = 106790
Step 119: 106790 + 905 = 107695
Step 120: 107695 + 905 = 108600
Step 121: 108600 + 905 = 109505
Step 122: 109505 + 905 = 110410
Step 123: 110410 + 905 = 111315
Step 124: 111315 + 905 = 112220
Step 125: 112220 + 905 = 113125
Step 126: 113125 + 905 = 114030
Step 127: 114030 + 905 = 114935
Step 128: 114935 + 905 = 115840
Step 129: 115840 + 905 = 116745
Step 130: 116745 + 905 = 117650
Step 131: 117650 + 905 = 118555
Step 132: 118555 + 905 = 119460
Step 133: 119460 + 905 = 120365
Step 134: 120365 + 905 = 121270
Step 135: 121270 + 905 = 122175
Step 136: 122175 + 905 = 123080
Step 137: 123080 + 905 = 123985
Step 138: 123985 + 905 = 124890
Step 139: 124890 + 905 = 125795
Step 140: 125795 + 905 = 126700
Step 141: 126700 + 905 = 127605
Step 142: 127605 + 905 = 128510
Step 143: 128510 + 905 = 129415

So, 905*143 = 129415