Let's roll up our sleeves and solve this. We have 142 and we're going to multiply it by 157, essentially adding 142 to itself 157 times.
Step 1: 0 + 142 = 142
Step 2: 142 + 142 = 284
Step 3: 284 + 142 = 426
Step 4: 426 + 142 = 568
Step 5: 568 + 142 = 710
Step 6: 710 + 142 = 852
Step 7: 852 + 142 = 994
Step 8: 994 + 142 = 1136
Step 9: 1136 + 142 = 1278
Step 10: 1278 + 142 = 1420
Step 11: 1420 + 142 = 1562
Step 12: 1562 + 142 = 1704
Step 13: 1704 + 142 = 1846
Step 14: 1846 + 142 = 1988
Step 15: 1988 + 142 = 2130
Step 16: 2130 + 142 = 2272
Step 17: 2272 + 142 = 2414
Step 18: 2414 + 142 = 2556
Step 19: 2556 + 142 = 2698
Step 20: 2698 + 142 = 2840
Step 21: 2840 + 142 = 2982
Step 22: 2982 + 142 = 3124
Step 23: 3124 + 142 = 3266
Step 24: 3266 + 142 = 3408
Step 25: 3408 + 142 = 3550
Step 26: 3550 + 142 = 3692
Step 27: 3692 + 142 = 3834
Step 28: 3834 + 142 = 3976
Step 29: 3976 + 142 = 4118
Step 30: 4118 + 142 = 4260
Step 31: 4260 + 142 = 4402
Step 32: 4402 + 142 = 4544
Step 33: 4544 + 142 = 4686
Step 34: 4686 + 142 = 4828
Step 35: 4828 + 142 = 4970
Step 36: 4970 + 142 = 5112
Step 37: 5112 + 142 = 5254
Step 38: 5254 + 142 = 5396
Step 39: 5396 + 142 = 5538
Step 40: 5538 + 142 = 5680
Step 41: 5680 + 142 = 5822
Step 42: 5822 + 142 = 5964
Step 43: 5964 + 142 = 6106
Step 44: 6106 + 142 = 6248
Step 45: 6248 + 142 = 6390
Step 46: 6390 + 142 = 6532
Step 47: 6532 + 142 = 6674
Step 48: 6674 + 142 = 6816
Step 49: 6816 + 142 = 6958
Step 50: 6958 + 142 = 7100
Step 51: 7100 + 142 = 7242
Step 52: 7242 + 142 = 7384
Step 53: 7384 + 142 = 7526
Step 54: 7526 + 142 = 7668
Step 55: 7668 + 142 = 7810
Step 56: 7810 + 142 = 7952
Step 57: 7952 + 142 = 8094
Step 58: 8094 + 142 = 8236
Step 59: 8236 + 142 = 8378
Step 60: 8378 + 142 = 8520
Step 61: 8520 + 142 = 8662
Step 62: 8662 + 142 = 8804
Step 63: 8804 + 142 = 8946
Step 64: 8946 + 142 = 9088
Step 65: 9088 + 142 = 9230
Step 66: 9230 + 142 = 9372
Step 67: 9372 + 142 = 9514
Step 68: 9514 + 142 = 9656
Step 69: 9656 + 142 = 9798
Step 70: 9798 + 142 = 9940
Step 71: 9940 + 142 = 10082
Step 72: 10082 + 142 = 10224
Step 73: 10224 + 142 = 10366
Step 74: 10366 + 142 = 10508
Step 75: 10508 + 142 = 10650
Step 76: 10650 + 142 = 10792
Step 77: 10792 + 142 = 10934
Step 78: 10934 + 142 = 11076
Step 79: 11076 + 142 = 11218
Step 80: 11218 + 142 = 11360
Step 81: 11360 + 142 = 11502
Step 82: 11502 + 142 = 11644
Step 83: 11644 + 142 = 11786
Step 84: 11786 + 142 = 11928
Step 85: 11928 + 142 = 12070
Step 86: 12070 + 142 = 12212
Step 87: 12212 + 142 = 12354
Step 88: 12354 + 142 = 12496
Step 89: 12496 + 142 = 12638
Step 90: 12638 + 142 = 12780
Step 91: 12780 + 142 = 12922
Step 92: 12922 + 142 = 13064
Step 93: 13064 + 142 = 13206
Step 94: 13206 + 142 = 13348
Step 95: 13348 + 142 = 13490
Step 96: 13490 + 142 = 13632
Step 97: 13632 + 142 = 13774
Step 98: 13774 + 142 = 13916
Step 99: 13916 + 142 = 14058
Step 100: 14058 + 142 = 14200
Step 101: 14200 + 142 = 14342
Step 102: 14342 + 142 = 14484
Step 103: 14484 + 142 = 14626
Step 104: 14626 + 142 = 14768
Step 105: 14768 + 142 = 14910
Step 106: 14910 + 142 = 15052
Step 107: 15052 + 142 = 15194
Step 108: 15194 + 142 = 15336
Step 109: 15336 + 142 = 15478
Step 110: 15478 + 142 = 15620
Step 111: 15620 + 142 = 15762
Step 112: 15762 + 142 = 15904
Step 113: 15904 + 142 = 16046
Step 114: 16046 + 142 = 16188
Step 115: 16188 + 142 = 16330
Step 116: 16330 + 142 = 16472
Step 117: 16472 + 142 = 16614
Step 118: 16614 + 142 = 16756
Step 119: 16756 + 142 = 16898
Step 120: 16898 + 142 = 17040
Step 121: 17040 + 142 = 17182
Step 122: 17182 + 142 = 17324
Step 123: 17324 + 142 = 17466
Step 124: 17466 + 142 = 17608
Step 125: 17608 + 142 = 17750
Step 126: 17750 + 142 = 17892
Step 127: 17892 + 142 = 18034
Step 128: 18034 + 142 = 18176
Step 129: 18176 + 142 = 18318
Step 130: 18318 + 142 = 18460
Step 131: 18460 + 142 = 18602
Step 132: 18602 + 142 = 18744
Step 133: 18744 + 142 = 18886
Step 134: 18886 + 142 = 19028
Step 135: 19028 + 142 = 19170
Step 136: 19170 + 142 = 19312
Step 137: 19312 + 142 = 19454
Step 138: 19454 + 142 = 19596
Step 139: 19596 + 142 = 19738
Step 140: 19738 + 142 = 19880
Step 141: 19880 + 142 = 20022
Step 142: 20022 + 142 = 20164
Step 143: 20164 + 142 = 20306
Step 144: 20306 + 142 = 20448
Step 145: 20448 + 142 = 20590
Step 146: 20590 + 142 = 20732
Step 147: 20732 + 142 = 20874
Step 148: 20874 + 142 = 21016
Step 149: 21016 + 142 = 21158
Step 150: 21158 + 142 = 21300
Step 151: 21300 + 142 = 21442
Step 152: 21442 + 142 = 21584
Step 153: 21584 + 142 = 21726
Step 154: 21726 + 142 = 21868
Step 155: 21868 + 142 = 22010
Step 156: 22010 + 142 = 22152
Step 157: 22152 + 142 = 22294

So, 142*157 = 22294