Alright, let's solve this math problem step by step. First, we have the number 823. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 158. So, we're going to take the number 823 and add it to itself 158 times.
Step 1: 0 + 823 = 823
Step 2: 823 + 823 = 1646
Step 3: 1646 + 823 = 2469
Step 4: 2469 + 823 = 3292
Step 5: 3292 + 823 = 4115
Step 6: 4115 + 823 = 4938
Step 7: 4938 + 823 = 5761
Step 8: 5761 + 823 = 6584
Step 9: 6584 + 823 = 7407
Step 10: 7407 + 823 = 8230
Step 11: 8230 + 823 = 9053
Step 12: 9053 + 823 = 9876
Step 13: 9876 + 823 = 10699
Step 14: 10699 + 823 = 11522
Step 15: 11522 + 823 = 12345
Step 16: 12345 + 823 = 13168
Step 17: 13168 + 823 = 13991
Step 18: 13991 + 823 = 14814
Step 19: 14814 + 823 = 15637
Step 20: 15637 + 823 = 16460
Step 21: 16460 + 823 = 17283
Step 22: 17283 + 823 = 18106
Step 23: 18106 + 823 = 18929
Step 24: 18929 + 823 = 19752
Step 25: 19752 + 823 = 20575
Step 26: 20575 + 823 = 21398
Step 27: 21398 + 823 = 22221
Step 28: 22221 + 823 = 23044
Step 29: 23044 + 823 = 23867
Step 30: 23867 + 823 = 24690
Step 31: 24690 + 823 = 25513
Step 32: 25513 + 823 = 26336
Step 33: 26336 + 823 = 27159
Step 34: 27159 + 823 = 27982
Step 35: 27982 + 823 = 28805
Step 36: 28805 + 823 = 29628
Step 37: 29628 + 823 = 30451
Step 38: 30451 + 823 = 31274
Step 39: 31274 + 823 = 32097
Step 40: 32097 + 823 = 32920
Step 41: 32920 + 823 = 33743
Step 42: 33743 + 823 = 34566
Step 43: 34566 + 823 = 35389
Step 44: 35389 + 823 = 36212
Step 45: 36212 + 823 = 37035
Step 46: 37035 + 823 = 37858
Step 47: 37858 + 823 = 38681
Step 48: 38681 + 823 = 39504
Step 49: 39504 + 823 = 40327
Step 50: 40327 + 823 = 41150
Step 51: 41150 + 823 = 41973
Step 52: 41973 + 823 = 42796
Step 53: 42796 + 823 = 43619
Step 54: 43619 + 823 = 44442
Step 55: 44442 + 823 = 45265
Step 56: 45265 + 823 = 46088
Step 57: 46088 + 823 = 46911
Step 58: 46911 + 823 = 47734
Step 59: 47734 + 823 = 48557
Step 60: 48557 + 823 = 49380
Step 61: 49380 + 823 = 50203
Step 62: 50203 + 823 = 51026
Step 63: 51026 + 823 = 51849
Step 64: 51849 + 823 = 52672
Step 65: 52672 + 823 = 53495
Step 66: 53495 + 823 = 54318
Step 67: 54318 + 823 = 55141
Step 68: 55141 + 823 = 55964
Step 69: 55964 + 823 = 56787
Step 70: 56787 + 823 = 57610
Step 71: 57610 + 823 = 58433
Step 72: 58433 + 823 = 59256
Step 73: 59256 + 823 = 60079
Step 74: 60079 + 823 = 60902
Step 75: 60902 + 823 = 61725
Step 76: 61725 + 823 = 62548
Step 77: 62548 + 823 = 63371
Step 78: 63371 + 823 = 64194
Step 79: 64194 + 823 = 65017
Step 80: 65017 + 823 = 65840
Step 81: 65840 + 823 = 66663
Step 82: 66663 + 823 = 67486
Step 83: 67486 + 823 = 68309
Step 84: 68309 + 823 = 69132
Step 85: 69132 + 823 = 69955
Step 86: 69955 + 823 = 70778
Step 87: 70778 + 823 = 71601
Step 88: 71601 + 823 = 72424
Step 89: 72424 + 823 = 73247
Step 90: 73247 + 823 = 74070
Step 91: 74070 + 823 = 74893
Step 92: 74893 + 823 = 75716
Step 93: 75716 + 823 = 76539
Step 94: 76539 + 823 = 77362
Step 95: 77362 + 823 = 78185
Step 96: 78185 + 823 = 79008
Step 97: 79008 + 823 = 79831
Step 98: 79831 + 823 = 80654
Step 99: 80654 + 823 = 81477
Step 100: 81477 + 823 = 82300
Step 101: 82300 + 823 = 83123
Step 102: 83123 + 823 = 83946
Step 103: 83946 + 823 = 84769
Step 104: 84769 + 823 = 85592
Step 105: 85592 + 823 = 86415
Step 106: 86415 + 823 = 87238
Step 107: 87238 + 823 = 88061
Step 108: 88061 + 823 = 88884
Step 109: 88884 + 823 = 89707
Step 110: 89707 + 823 = 90530
Step 111: 90530 + 823 = 91353
Step 112: 91353 + 823 = 92176
Step 113: 92176 + 823 = 92999
Step 114: 92999 + 823 = 93822
Step 115: 93822 + 823 = 94645
Step 116: 94645 + 823 = 95468
Step 117: 95468 + 823 = 96291
Step 118: 96291 + 823 = 97114
Step 119: 97114 + 823 = 97937
Step 120: 97937 + 823 = 98760
Step 121: 98760 + 823 = 99583
Step 122: 99583 + 823 = 100406
Step 123: 100406 + 823 = 101229
Step 124: 101229 + 823 = 102052
Step 125: 102052 + 823 = 102875
Step 126: 102875 + 823 = 103698
Step 127: 103698 + 823 = 104521
Step 128: 104521 + 823 = 105344
Step 129: 105344 + 823 = 106167
Step 130: 106167 + 823 = 106990
Step 131: 106990 + 823 = 107813
Step 132: 107813 + 823 = 108636
Step 133: 108636 + 823 = 109459
Step 134: 109459 + 823 = 110282
Step 135: 110282 + 823 = 111105
Step 136: 111105 + 823 = 111928
Step 137: 111928 + 823 = 112751
Step 138: 112751 + 823 = 113574
Step 139: 113574 + 823 = 114397
Step 140: 114397 + 823 = 115220
Step 141: 115220 + 823 = 116043
Step 142: 116043 + 823 = 116866
Step 143: 116866 + 823 = 117689
Step 144: 117689 + 823 = 118512
Step 145: 118512 + 823 = 119335
Step 146: 119335 + 823 = 120158
Step 147: 120158 + 823 = 120981
Step 148: 120981 + 823 = 121804
Step 149: 121804 + 823 = 122627
Step 150: 122627 + 823 = 123450
Step 151: 123450 + 823 = 124273
Step 152: 124273 + 823 = 125096
Step 153: 125096 + 823 = 125919
Step 154: 125919 + 823 = 126742
Step 155: 126742 + 823 = 127565
Step 156: 127565 + 823 = 128388
Step 157: 128388 + 823 = 129211
Step 158: 129211 + 823 = 130034

So, 823*158 = 130034