Let's roll up our sleeves and solve this. We have 907 and we're going to multiply it by 153, essentially adding 907 to itself 153 times.
Step 1: 0 + 907 = 907
Step 2: 907 + 907 = 1814
Step 3: 1814 + 907 = 2721
Step 4: 2721 + 907 = 3628
Step 5: 3628 + 907 = 4535
Step 6: 4535 + 907 = 5442
Step 7: 5442 + 907 = 6349
Step 8: 6349 + 907 = 7256
Step 9: 7256 + 907 = 8163
Step 10: 8163 + 907 = 9070
Step 11: 9070 + 907 = 9977
Step 12: 9977 + 907 = 10884
Step 13: 10884 + 907 = 11791
Step 14: 11791 + 907 = 12698
Step 15: 12698 + 907 = 13605
Step 16: 13605 + 907 = 14512
Step 17: 14512 + 907 = 15419
Step 18: 15419 + 907 = 16326
Step 19: 16326 + 907 = 17233
Step 20: 17233 + 907 = 18140
Step 21: 18140 + 907 = 19047
Step 22: 19047 + 907 = 19954
Step 23: 19954 + 907 = 20861
Step 24: 20861 + 907 = 21768
Step 25: 21768 + 907 = 22675
Step 26: 22675 + 907 = 23582
Step 27: 23582 + 907 = 24489
Step 28: 24489 + 907 = 25396
Step 29: 25396 + 907 = 26303
Step 30: 26303 + 907 = 27210
Step 31: 27210 + 907 = 28117
Step 32: 28117 + 907 = 29024
Step 33: 29024 + 907 = 29931
Step 34: 29931 + 907 = 30838
Step 35: 30838 + 907 = 31745
Step 36: 31745 + 907 = 32652
Step 37: 32652 + 907 = 33559
Step 38: 33559 + 907 = 34466
Step 39: 34466 + 907 = 35373
Step 40: 35373 + 907 = 36280
Step 41: 36280 + 907 = 37187
Step 42: 37187 + 907 = 38094
Step 43: 38094 + 907 = 39001
Step 44: 39001 + 907 = 39908
Step 45: 39908 + 907 = 40815
Step 46: 40815 + 907 = 41722
Step 47: 41722 + 907 = 42629
Step 48: 42629 + 907 = 43536
Step 49: 43536 + 907 = 44443
Step 50: 44443 + 907 = 45350
Step 51: 45350 + 907 = 46257
Step 52: 46257 + 907 = 47164
Step 53: 47164 + 907 = 48071
Step 54: 48071 + 907 = 48978
Step 55: 48978 + 907 = 49885
Step 56: 49885 + 907 = 50792
Step 57: 50792 + 907 = 51699
Step 58: 51699 + 907 = 52606
Step 59: 52606 + 907 = 53513
Step 60: 53513 + 907 = 54420
Step 61: 54420 + 907 = 55327
Step 62: 55327 + 907 = 56234
Step 63: 56234 + 907 = 57141
Step 64: 57141 + 907 = 58048
Step 65: 58048 + 907 = 58955
Step 66: 58955 + 907 = 59862
Step 67: 59862 + 907 = 60769
Step 68: 60769 + 907 = 61676
Step 69: 61676 + 907 = 62583
Step 70: 62583 + 907 = 63490
Step 71: 63490 + 907 = 64397
Step 72: 64397 + 907 = 65304
Step 73: 65304 + 907 = 66211
Step 74: 66211 + 907 = 67118
Step 75: 67118 + 907 = 68025
Step 76: 68025 + 907 = 68932
Step 77: 68932 + 907 = 69839
Step 78: 69839 + 907 = 70746
Step 79: 70746 + 907 = 71653
Step 80: 71653 + 907 = 72560
Step 81: 72560 + 907 = 73467
Step 82: 73467 + 907 = 74374
Step 83: 74374 + 907 = 75281
Step 84: 75281 + 907 = 76188
Step 85: 76188 + 907 = 77095
Step 86: 77095 + 907 = 78002
Step 87: 78002 + 907 = 78909
Step 88: 78909 + 907 = 79816
Step 89: 79816 + 907 = 80723
Step 90: 80723 + 907 = 81630
Step 91: 81630 + 907 = 82537
Step 92: 82537 + 907 = 83444
Step 93: 83444 + 907 = 84351
Step 94: 84351 + 907 = 85258
Step 95: 85258 + 907 = 86165
Step 96: 86165 + 907 = 87072
Step 97: 87072 + 907 = 87979
Step 98: 87979 + 907 = 88886
Step 99: 88886 + 907 = 89793
Step 100: 89793 + 907 = 90700
Step 101: 90700 + 907 = 91607
Step 102: 91607 + 907 = 92514
Step 103: 92514 + 907 = 93421
Step 104: 93421 + 907 = 94328
Step 105: 94328 + 907 = 95235
Step 106: 95235 + 907 = 96142
Step 107: 96142 + 907 = 97049
Step 108: 97049 + 907 = 97956
Step 109: 97956 + 907 = 98863
Step 110: 98863 + 907 = 99770
Step 111: 99770 + 907 = 100677
Step 112: 100677 + 907 = 101584
Step 113: 101584 + 907 = 102491
Step 114: 102491 + 907 = 103398
Step 115: 103398 + 907 = 104305
Step 116: 104305 + 907 = 105212
Step 117: 105212 + 907 = 106119
Step 118: 106119 + 907 = 107026
Step 119: 107026 + 907 = 107933
Step 120: 107933 + 907 = 108840
Step 121: 108840 + 907 = 109747
Step 122: 109747 + 907 = 110654
Step 123: 110654 + 907 = 111561
Step 124: 111561 + 907 = 112468
Step 125: 112468 + 907 = 113375
Step 126: 113375 + 907 = 114282
Step 127: 114282 + 907 = 115189
Step 128: 115189 + 907 = 116096
Step 129: 116096 + 907 = 117003
Step 130: 117003 + 907 = 117910
Step 131: 117910 + 907 = 118817
Step 132: 118817 + 907 = 119724
Step 133: 119724 + 907 = 120631
Step 134: 120631 + 907 = 121538
Step 135: 121538 + 907 = 122445
Step 136: 122445 + 907 = 123352
Step 137: 123352 + 907 = 124259
Step 138: 124259 + 907 = 125166
Step 139: 125166 + 907 = 126073
Step 140: 126073 + 907 = 126980
Step 141: 126980 + 907 = 127887
Step 142: 127887 + 907 = 128794
Step 143: 128794 + 907 = 129701
Step 144: 129701 + 907 = 130608
Step 145: 130608 + 907 = 131515
Step 146: 131515 + 907 = 132422
Step 147: 132422 + 907 = 133329
Step 148: 133329 + 907 = 134236
Step 149: 134236 + 907 = 135143
Step 150: 135143 + 907 = 136050
Step 151: 136050 + 907 = 136957
Step 152: 136957 + 907 = 137864
Step 153: 137864 + 907 = 138771

So, 907*153 = 138771