OK, let's work through this together. We're starting with 408 and we're going to multiply it by 158, which means we add 408 to itself 158 times.
Step 1: 0 + 408 = 408
Step 2: 408 + 408 = 816
Step 3: 816 + 408 = 1224
Step 4: 1224 + 408 = 1632
Step 5: 1632 + 408 = 2040
Step 6: 2040 + 408 = 2448
Step 7: 2448 + 408 = 2856
Step 8: 2856 + 408 = 3264
Step 9: 3264 + 408 = 3672
Step 10: 3672 + 408 = 4080
Step 11: 4080 + 408 = 4488
Step 12: 4488 + 408 = 4896
Step 13: 4896 + 408 = 5304
Step 14: 5304 + 408 = 5712
Step 15: 5712 + 408 = 6120
Step 16: 6120 + 408 = 6528
Step 17: 6528 + 408 = 6936
Step 18: 6936 + 408 = 7344
Step 19: 7344 + 408 = 7752
Step 20: 7752 + 408 = 8160
Step 21: 8160 + 408 = 8568
Step 22: 8568 + 408 = 8976
Step 23: 8976 + 408 = 9384
Step 24: 9384 + 408 = 9792
Step 25: 9792 + 408 = 10200
Step 26: 10200 + 408 = 10608
Step 27: 10608 + 408 = 11016
Step 28: 11016 + 408 = 11424
Step 29: 11424 + 408 = 11832
Step 30: 11832 + 408 = 12240
Step 31: 12240 + 408 = 12648
Step 32: 12648 + 408 = 13056
Step 33: 13056 + 408 = 13464
Step 34: 13464 + 408 = 13872
Step 35: 13872 + 408 = 14280
Step 36: 14280 + 408 = 14688
Step 37: 14688 + 408 = 15096
Step 38: 15096 + 408 = 15504
Step 39: 15504 + 408 = 15912
Step 40: 15912 + 408 = 16320
Step 41: 16320 + 408 = 16728
Step 42: 16728 + 408 = 17136
Step 43: 17136 + 408 = 17544
Step 44: 17544 + 408 = 17952
Step 45: 17952 + 408 = 18360
Step 46: 18360 + 408 = 18768
Step 47: 18768 + 408 = 19176
Step 48: 19176 + 408 = 19584
Step 49: 19584 + 408 = 19992
Step 50: 19992 + 408 = 20400
Step 51: 20400 + 408 = 20808
Step 52: 20808 + 408 = 21216
Step 53: 21216 + 408 = 21624
Step 54: 21624 + 408 = 22032
Step 55: 22032 + 408 = 22440
Step 56: 22440 + 408 = 22848
Step 57: 22848 + 408 = 23256
Step 58: 23256 + 408 = 23664
Step 59: 23664 + 408 = 24072
Step 60: 24072 + 408 = 24480
Step 61: 24480 + 408 = 24888
Step 62: 24888 + 408 = 25296
Step 63: 25296 + 408 = 25704
Step 64: 25704 + 408 = 26112
Step 65: 26112 + 408 = 26520
Step 66: 26520 + 408 = 26928
Step 67: 26928 + 408 = 27336
Step 68: 27336 + 408 = 27744
Step 69: 27744 + 408 = 28152
Step 70: 28152 + 408 = 28560
Step 71: 28560 + 408 = 28968
Step 72: 28968 + 408 = 29376
Step 73: 29376 + 408 = 29784
Step 74: 29784 + 408 = 30192
Step 75: 30192 + 408 = 30600
Step 76: 30600 + 408 = 31008
Step 77: 31008 + 408 = 31416
Step 78: 31416 + 408 = 31824
Step 79: 31824 + 408 = 32232
Step 80: 32232 + 408 = 32640
Step 81: 32640 + 408 = 33048
Step 82: 33048 + 408 = 33456
Step 83: 33456 + 408 = 33864
Step 84: 33864 + 408 = 34272
Step 85: 34272 + 408 = 34680
Step 86: 34680 + 408 = 35088
Step 87: 35088 + 408 = 35496
Step 88: 35496 + 408 = 35904
Step 89: 35904 + 408 = 36312
Step 90: 36312 + 408 = 36720
Step 91: 36720 + 408 = 37128
Step 92: 37128 + 408 = 37536
Step 93: 37536 + 408 = 37944
Step 94: 37944 + 408 = 38352
Step 95: 38352 + 408 = 38760
Step 96: 38760 + 408 = 39168
Step 97: 39168 + 408 = 39576
Step 98: 39576 + 408 = 39984
Step 99: 39984 + 408 = 40392
Step 100: 40392 + 408 = 40800
Step 101: 40800 + 408 = 41208
Step 102: 41208 + 408 = 41616
Step 103: 41616 + 408 = 42024
Step 104: 42024 + 408 = 42432
Step 105: 42432 + 408 = 42840
Step 106: 42840 + 408 = 43248
Step 107: 43248 + 408 = 43656
Step 108: 43656 + 408 = 44064
Step 109: 44064 + 408 = 44472
Step 110: 44472 + 408 = 44880
Step 111: 44880 + 408 = 45288
Step 112: 45288 + 408 = 45696
Step 113: 45696 + 408 = 46104
Step 114: 46104 + 408 = 46512
Step 115: 46512 + 408 = 46920
Step 116: 46920 + 408 = 47328
Step 117: 47328 + 408 = 47736
Step 118: 47736 + 408 = 48144
Step 119: 48144 + 408 = 48552
Step 120: 48552 + 408 = 48960
Step 121: 48960 + 408 = 49368
Step 122: 49368 + 408 = 49776
Step 123: 49776 + 408 = 50184
Step 124: 50184 + 408 = 50592
Step 125: 50592 + 408 = 51000
Step 126: 51000 + 408 = 51408
Step 127: 51408 + 408 = 51816
Step 128: 51816 + 408 = 52224
Step 129: 52224 + 408 = 52632
Step 130: 52632 + 408 = 53040
Step 131: 53040 + 408 = 53448
Step 132: 53448 + 408 = 53856
Step 133: 53856 + 408 = 54264
Step 134: 54264 + 408 = 54672
Step 135: 54672 + 408 = 55080
Step 136: 55080 + 408 = 55488
Step 137: 55488 + 408 = 55896
Step 138: 55896 + 408 = 56304
Step 139: 56304 + 408 = 56712
Step 140: 56712 + 408 = 57120
Step 141: 57120 + 408 = 57528
Step 142: 57528 + 408 = 57936
Step 143: 57936 + 408 = 58344
Step 144: 58344 + 408 = 58752
Step 145: 58752 + 408 = 59160
Step 146: 59160 + 408 = 59568
Step 147: 59568 + 408 = 59976
Step 148: 59976 + 408 = 60384
Step 149: 60384 + 408 = 60792
Step 150: 60792 + 408 = 61200
Step 151: 61200 + 408 = 61608
Step 152: 61608 + 408 = 62016
Step 153: 62016 + 408 = 62424
Step 154: 62424 + 408 = 62832
Step 155: 62832 + 408 = 63240
Step 156: 63240 + 408 = 63648
Step 157: 63648 + 408 = 64056
Step 158: 64056 + 408 = 64464

So, 408*158 = 64464